Antisense rna technology
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Antisense RNA is the complementary RNA to the protein-coding messenger mRNA. The antisense mRNA binds to sense mRNA and the translation was restricted, that is called translation arrest. The nature antisense RNA technology present in hok &sok in E.coli R1 plasmid. The artificial or purpose antisense RNA technology best example is flavr savr tomato.
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Labelling of dna
This document discusses nucleic acid probes and their use in hybridization experiments. It notes that probes are short sequences of nucleotides that bind to specific target sequences. The degree of homology between the probe and target determines how stable the hybridization is. Probes can range in size from 10 to over 10,000 nucleotide bases, with most common probes being 14 to 40 bases. Short probes hybridize quickly but have less specificity, while longer probes hybridize more stably. The document then describes different methods for labeling probes, including nick translation, primer extension, RNA polymerase transcription, end-labeling, and direct labeling. It also discusses factors that affect probe specificity and hybridization conditions.
Ri Plasmid
The Ri plasmid is a plasmid found in Agrobacterium rhizogenes bacteria that causes hairy root disease in plants. The plasmid contains genes that allow it to integrate portions of its DNA (T-DNA regions) into the plant genome. These integrated genes cause uncontrolled root growth and the formation of hairy roots. The Ri plasmid shares similarities with the Ti plasmid found in Agrobacterium tumefaciens, including virulence genes that mediate the transfer of T-DNA into plant cells and opine synthesis genes. Integration of the T-DNA from the Ri plasmid alters plant hormone production and induces hairy root formation.
Shuttle vector
1. Yeast plasmids like the 2 micron circle have been extensively studied and developed into yeast cloning vectors.
2. Shuttle vectors like YEp vectors contain selectable marker genes like LEU2 and bacterial plasmid origins of replication like pBR322, allowing them to replicate in both E. coli and yeast.
3. The 2 micron circle is a 6kb endogenous yeast plasmid that replicates autonomously through an ARS sequence and is maintained at 50-100 copies per cell.
Ti plasmid
The document summarizes key information about Ti plasmids, which are plasmids found in Agrobacterium tumefaciens that cause crown gall disease in plants. The Ti plasmid transfers a segment of DNA called T-DNA into the host plant genome, integrating genes that cause tumor formation. The plasmid has regions for T-DNA, virulence genes needed for transfer, and sometimes opine catabolism genes. Ti plasmids are used to create transgenic plants by replacing the tumor genes with a gene of interest in the T-DNA.
Reporter genes
1) Reporter genes produce a detectable phenotype that allows transformed cells to be easily identified and selected. They are useful tools for studying gene expression.
2) Common reporter genes include GFP and luciferase, which produce fluorescent and luminescent proteins, respectively, that can be quantified.
3) Selectable marker genes, like antibiotic resistance genes, allow transformed cells to survive selective conditions that kill untransformed cells. This enables isolation of transformed cells.
Antisense rna technology
Antisense RNA technology uses single-stranded RNA complementary to messenger RNA to inhibit translation by binding to the mRNA and activating RNase H degradation of the mRNA. While RNAi uses Dicer enzymes, antisense RNA relies on RNase H. The first FDA approved genetically modified food, the Flavr-Savr tomato, used antisense RNA to inhibit the polygalacturonase enzyme and extend tomato shelf life. NIPGR developed tomatoes that could last 45 days using antisense RNA to silence genes responsible for loss of firmness during ripening. Antisense therapy is also being researched to treat diseases by introducing antisense RNA to pathogenic genes.
Virus resistance plant, production
introduction
What is virus
What is virus resistance plant
History
Gene use for develop virus resistance plant
Coat protein gene
cDNA of satellite RNA
Defective viral genome
Antisense RNA approach and
Ribozyme â mediated protection
conclusion
References
Antisense RNA Technology
The document discusses gene silencing techniques such as antisense RNA technology and RNA interference (RNAi). It provides a brief history of discoveries in this field dating back to the 1990s. It explains the mechanisms and applications of transcriptional gene silencing and post-transcriptional gene silencing. Examples are given of using these techniques to modify properties of crops like tomatoes. While offering potential benefits to research and medicine, challenges remain around delivery methods and off-target effects.
Recommended
Labelling of dna
This document discusses nucleic acid probes and their use in hybridization experiments. It notes that probes are short sequences of nucleotides that bind to specific target sequences. The degree of homology between the probe and target determines how stable the hybridization is. Probes can range in size from 10 to over 10,000 nucleotide bases, with most common probes being 14 to 40 bases. Short probes hybridize quickly but have less specificity, while longer probes hybridize more stably. The document then describes different methods for labeling probes, including nick translation, primer extension, RNA polymerase transcription, end-labeling, and direct labeling. It also discusses factors that affect probe specificity and hybridization conditions.
Ri Plasmid
The Ri plasmid is a plasmid found in Agrobacterium rhizogenes bacteria that causes hairy root disease in plants. The plasmid contains genes that allow it to integrate portions of its DNA (T-DNA regions) into the plant genome. These integrated genes cause uncontrolled root growth and the formation of hairy roots. The Ri plasmid shares similarities with the Ti plasmid found in Agrobacterium tumefaciens, including virulence genes that mediate the transfer of T-DNA into plant cells and opine synthesis genes. Integration of the T-DNA from the Ri plasmid alters plant hormone production and induces hairy root formation.
Shuttle vector
1. Yeast plasmids like the 2 micron circle have been extensively studied and developed into yeast cloning vectors.
2. Shuttle vectors like YEp vectors contain selectable marker genes like LEU2 and bacterial plasmid origins of replication like pBR322, allowing them to replicate in both E. coli and yeast.
3. The 2 micron circle is a 6kb endogenous yeast plasmid that replicates autonomously through an ARS sequence and is maintained at 50-100 copies per cell.
Ti plasmid
The document summarizes key information about Ti plasmids, which are plasmids found in Agrobacterium tumefaciens that cause crown gall disease in plants. The Ti plasmid transfers a segment of DNA called T-DNA into the host plant genome, integrating genes that cause tumor formation. The plasmid has regions for T-DNA, virulence genes needed for transfer, and sometimes opine catabolism genes. Ti plasmids are used to create transgenic plants by replacing the tumor genes with a gene of interest in the T-DNA.
Reporter genes
1) Reporter genes produce a detectable phenotype that allows transformed cells to be easily identified and selected. They are useful tools for studying gene expression.
2) Common reporter genes include GFP and luciferase, which produce fluorescent and luminescent proteins, respectively, that can be quantified.
3) Selectable marker genes, like antibiotic resistance genes, allow transformed cells to survive selective conditions that kill untransformed cells. This enables isolation of transformed cells.
Antisense rna technology
Antisense RNA technology uses single-stranded RNA complementary to messenger RNA to inhibit translation by binding to the mRNA and activating RNase H degradation of the mRNA. While RNAi uses Dicer enzymes, antisense RNA relies on RNase H. The first FDA approved genetically modified food, the Flavr-Savr tomato, used antisense RNA to inhibit the polygalacturonase enzyme and extend tomato shelf life. NIPGR developed tomatoes that could last 45 days using antisense RNA to silence genes responsible for loss of firmness during ripening. Antisense therapy is also being researched to treat diseases by introducing antisense RNA to pathogenic genes.
Virus resistance plant, production
introduction
What is virus
What is virus resistance plant
History
Gene use for develop virus resistance plant
Coat protein gene
cDNA of satellite RNA
Defective viral genome
Antisense RNA approach and
Ribozyme â mediated protection
conclusion
References
Antisense RNA Technology
The document discusses gene silencing techniques such as antisense RNA technology and RNA interference (RNAi). It provides a brief history of discoveries in this field dating back to the 1990s. It explains the mechanisms and applications of transcriptional gene silencing and post-transcriptional gene silencing. Examples are given of using these techniques to modify properties of crops like tomatoes. While offering potential benefits to research and medicine, challenges remain around delivery methods and off-target effects.
Gene knockout
Gene knockout is a technique used to study gene function by inactivating genes in living organisms. It involves using gene targeting to disrupt a gene, preventing it from functioning normally. Researchers developed methods for knocking out genes in mice using embryonic stem cells, which won them the 2007 Nobel Prize in Physiology or Medicine. The basic process involves engineering a construct to disrupt a target gene, introducing it into embryonic stem cells, generating a knockout mouse, and studying the effects of the disrupted gene. Gene knockout is a valuable tool for biomedical research and understanding disease mechanisms.
Genome sequencing
The document discusses genome sequencing and related topics. It begins by defining what a genome is - the complete set of DNA in an organism. It then discusses the different types of genomes, such as prokaryotic and eukaryotic, including nuclear, mitochondrial, and chloroplast genomes. The document also defines genomics as the comprehensive study of whole genomes and all gene interactions, distinguishing it from traditional genetics which focuses on single genes. It outlines some key milestones in genomic sequencing and the technical foundations that enabled sequencing whole genomes. Finally, it describes the main approaches used for genome sequencing projects, including hierarchical shotgun sequencing and whole genome shotgun sequencing.
CDNA Library preparation. ppt for Jamil sir
cDNA is produced from mRNA found in the nucleus and contains only the expressed genes of an organism. To create a cDNA library, mRNA is first extracted and purified from a cell, then reverse transcribed into cDNA using an oligo-dT primer that binds to the poly-A tail. The resulting single-stranded cDNA is converted into double-stranded DNA and cloned into plasmids in bacteria. cDNA libraries are useful for reproducing eukaryotic genomes without introns, expressing eukaryotic genes in prokaryotes, discovering novel genes, and studying alternative splicing in different cells.
HOMOPOLYMER TAILING.pptx
This document is a seminar submission on the topic of homopolymer tailing. It introduces homopolymer tailing as a method for joining DNA molecules by annealing complementary homopolymer sequences. Specifically, it involves adding homopolymer sequences like oligo(dA) to the 3' ends of one DNA molecule and complementary sequences like oligo(dT) to another molecule. This is done using the enzyme terminal deoxynucleotidyl transferase. The molecules can then be incubated to allow the complementary homopolymer sequences to anneal together via hydrogen bonding. Common applications include using poly dC tails on vectors and poly dG tails on DNA fragments to be cloned, in order to ligate the two molecules together
cDNA Library Construction
Creation of a cDNA library starts with mRNA instead of DNA. Messenger RNA carries encoded information from DNA to ribosomes for translation into protein. To create a cDNA library, these mRNA molecules are treated with the enzyme reverse transcriptase, which is used to make a DNA copy of an mRNA (i.e., cDNA). A cDNA library represents a sampling of the transcribed genes, but a genomic library includes untranscribed regions.
cohesive and blunt end ligation
This document discusses various methods for ligating DNA fragments, including blunt end ligation, sticky end ligation using linkers or adaptors, and homopolymeric tailing. Blunt end ligation is less efficient than sticky end ligation. Linkers and adaptors are oligonucleotides used to create sticky ends for ligation, while homopolymeric tailing uses terminal transferase to add homopolymer tails to blunt ends before ligation. The goal is to efficiently join vector and insert DNA fragments for recombinant DNA construction.
Transgenic plants
Transgenic plants are plants that have been genetically modified using genetic engineering techniques to introduce new traits. The goal is to insert desirable genes from other organisms to produce crops with improved traits like pest or disease resistance, increased yield, or tolerance to environmental stresses. Some examples of transgenic crops include insect-resistant corn and cotton, herbicide-resistant soybeans, and golden rice which is enriched with vitamin A. While transgenic crops offer advantages to farmers and consumers, some concerns exist around their impact on human health, the environment, and traditional farming practices. Ongoing research continues to assess both the promises and risks of this emerging agricultural technology.
Marker free transgenic strategy
This presentation discusses strategies for developing transgenic plants without selectable marker genes. Marker genes are commonly used to identify transformed cells but can be problematic for public acceptance and future transformations. Methods described for producing marker-free transgenics include the MAT system which uses oncogenes for selection instead of antibiotics, site-specific recombination systems which flank the marker gene for later excision, and transposon-based systems which separate the gene of interest from the marker gene. While several viable methods exist, more work is still needed before marker-free crops can be commercialized. Removing marker genes supports multiple-gene stacking and improves public acceptance of transgenic technologies.
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Genetic manipulation of plant and animal cells have to be confirmed for further application. One such confirmatory method is the use of stains/dyes which produces fluorescence when the recombination is successful.
ENZYMES IN RECOMBINANT DNA TECHNOLOGY
DNA modifying enzymes play important roles in recombinant DNA technology. DNA polymerase synthesizes DNA from deoxyribonucleotides and is essential for DNA replication. It consists of subunits that carry out polymerase and exonuclease activities. Reverse transcriptase generates cDNA from an RNA template. Alkaline phosphatase, phosphatase, kinase and methyltransferases modify DNA through addition or removal of phosphate groups or methyl groups and are used in cloning experiments and DNA sequencing. Terminal transferase adds nucleotides to DNA ends. Restriction enzymes are inhibited by DNA methylation.
Genomic library
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Insect resisance ppt
1. The seminar discusses developing transgenic plants resistant to insects through the transfer of resistance genes from microorganisms, higher plants, and animals into crop plants.
2. Major objectives of plant biotechnology are to develop plants resistant to biotic and abiotic stresses. Resistance to insects has been achieved by introducing genes encoding Bt toxins from Bacillus thuringiensis and other insecticidal proteins.
3. Useful genes have been isolated from microbes like B. thuringiensis, higher plants like beans and tobacco, and animals like mammals. These genes have been successfully used to engineer insect-resistant crops like cotton, potato, tomato, and tobacco.
Gene transformation methods
Transformation is the process of altering an organism's genetic makeup by inserting new genes. Common transformation methods include Agrobacterium-mediated transformation, particle bombardment, protoplast transformation using polyethylene glycol or electroporation, and fibre-mediated DNA delivery. Agrobacterium transformation involves the bacteria transferring T-DNA from its Ti plasmid into the plant genome, while direct methods introduce naked DNA into plant cells using physical methods like particle bombardment or chemical treatments that make cell membranes permeable. Transformation allows improving crop traits like yield and stress resistance.
Organ culture- animal tissue culture
Organ culture involves maintaining small fragments of whole organs or tissues in culture media while retaining their three-dimensional structure and spatial distribution of cells. There are several methods of organ culture including culturing on plasma clots, agar, liquid media, or raft methods. Organ culture has various applications and allows studying cell interactions in a way that mimics the in vivo organ. It is currently being used to develop replacement organs and tissues for applications such as growing bladders, lungs, and heart patches. While progress is being made, developing fully functional human organs remains a challenge.
Transgenic plants ppt
Basic information about Transgenic plants, their need , process of making transgenics and use of transgenics
T dna & transposone tagging 1 (2)
Gene tagging uses recognizable DNA fragments like T-DNA or transposons to disrupt gene function and identify genes responsible for mutant phenotypes. T-DNA tagging in plants involves random integration of Agrobacterium T-DNA that can disrupt genes and create mutants. Transposon tagging relies on the ability of transposons to move within genomes and disrupt gene function. Both techniques have been used successfully to isolate numerous plant genes involved in traits like color and development.
Selectable marker genes
The document discusses selectable marker genes that are commonly used in plant transformation systems. Selectable marker genes are included in transformation vectors along with the target gene of interest. They confer resistance to transformed cells when grown on media containing toxic substances like antibiotics, herbicides, or antimetabolites. This allows transformed cells to survive while non-transformed cells die. There are three main categories of selectable marker genes: antibiotic resistance genes, antimetabolite marker genes, and herbicide resistance genes. Common examples of genes used include nptII for kanamycin resistance, pat/bar for phosphinothricin/glufosinate resistance, and epsps/aroA for glyphosate resistance.
ZINC FINGER NUCLEASE TECHNOLOGY
Zinc finger nucleases (ZFNs) allow for highly targeted editing of the genome. ZFNs consist of a DNA-binding domain made of zinc finger proteins and a DNA-cleaving domain. The ZFN pair binds to a target site and creates a double-strand break, which the cell repairs through non-homologous end joining or homologous recombination, enabling gene knockouts or targeted changes. ZFNs work in many cell types and animal models, providing a more efficient alternative to traditional transgenic techniques. They have applications in functional genomics, cell line engineering, and animal model generation.
Virus induced gene silencing
Virus-induced gene silencing (VIGS) is a technique that uses a viral vector carrying a fragment of a plant gene of interest to induce gene silencing. When the virus infects the plant, double-stranded RNA is produced from the viral genome and plant gene fragment, which is cleaved by the plant's dicer enzyme into siRNAs. These siRNAs are incorporated into the RISC complex and guide mRNA degradation of the targeted endogenous gene. Examples discussed were using tobacco rattle virus for VIGS in Nicotiana benthamiana and silencing tomato genes involved in the GABA pathway to study their roles in salt tolerance.
Chloroplast engineering
This document summarizes research on chloroplast engineering for various applications. Chloroplasts naturally contain their own DNA and can be genetically engineered via homologous recombination. This allows for high levels of transgene expression without gene silencing effects. The document discusses how chloroplasts have been engineered for herbicide resistance, pathogen resistance, drought tolerance, and production of recombinant proteins. While chloroplast engineering holds promise, limitations include lack of expression in non-green cells and full genome sequence information for some species.
Antisense RNA technology
anti sense RNA technology is one the method for gene silencing. it found very effective making Flavr savr tomato. hope this ppt will help you.
Regulation of gene expression.pdf
Regulation of gene expression.
It can be helpful for the students of Biotechnology, Genetics, Molecular Biology, Microbiology and othe Biology related courses.
If you've got any queries, you can directly mail me to pratimasingdan@gmail.com.
I hope this will help you a lot.
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Gene knockout
Gene knockout is a technique used to study gene function by inactivating genes in living organisms. It involves using gene targeting to disrupt a gene, preventing it from functioning normally. Researchers developed methods for knocking out genes in mice using embryonic stem cells, which won them the 2007 Nobel Prize in Physiology or Medicine. The basic process involves engineering a construct to disrupt a target gene, introducing it into embryonic stem cells, generating a knockout mouse, and studying the effects of the disrupted gene. Gene knockout is a valuable tool for biomedical research and understanding disease mechanisms.
Genome sequencing
The document discusses genome sequencing and related topics. It begins by defining what a genome is - the complete set of DNA in an organism. It then discusses the different types of genomes, such as prokaryotic and eukaryotic, including nuclear, mitochondrial, and chloroplast genomes. The document also defines genomics as the comprehensive study of whole genomes and all gene interactions, distinguishing it from traditional genetics which focuses on single genes. It outlines some key milestones in genomic sequencing and the technical foundations that enabled sequencing whole genomes. Finally, it describes the main approaches used for genome sequencing projects, including hierarchical shotgun sequencing and whole genome shotgun sequencing.
CDNA Library preparation. ppt for Jamil sir
cDNA is produced from mRNA found in the nucleus and contains only the expressed genes of an organism. To create a cDNA library, mRNA is first extracted and purified from a cell, then reverse transcribed into cDNA using an oligo-dT primer that binds to the poly-A tail. The resulting single-stranded cDNA is converted into double-stranded DNA and cloned into plasmids in bacteria. cDNA libraries are useful for reproducing eukaryotic genomes without introns, expressing eukaryotic genes in prokaryotes, discovering novel genes, and studying alternative splicing in different cells.
HOMOPOLYMER TAILING.pptx
This document is a seminar submission on the topic of homopolymer tailing. It introduces homopolymer tailing as a method for joining DNA molecules by annealing complementary homopolymer sequences. Specifically, it involves adding homopolymer sequences like oligo(dA) to the 3' ends of one DNA molecule and complementary sequences like oligo(dT) to another molecule. This is done using the enzyme terminal deoxynucleotidyl transferase. The molecules can then be incubated to allow the complementary homopolymer sequences to anneal together via hydrogen bonding. Common applications include using poly dC tails on vectors and poly dG tails on DNA fragments to be cloned, in order to ligate the two molecules together
cDNA Library Construction
Creation of a cDNA library starts with mRNA instead of DNA. Messenger RNA carries encoded information from DNA to ribosomes for translation into protein. To create a cDNA library, these mRNA molecules are treated with the enzyme reverse transcriptase, which is used to make a DNA copy of an mRNA (i.e., cDNA). A cDNA library represents a sampling of the transcribed genes, but a genomic library includes untranscribed regions.
cohesive and blunt end ligation
This document discusses various methods for ligating DNA fragments, including blunt end ligation, sticky end ligation using linkers or adaptors, and homopolymeric tailing. Blunt end ligation is less efficient than sticky end ligation. Linkers and adaptors are oligonucleotides used to create sticky ends for ligation, while homopolymeric tailing uses terminal transferase to add homopolymer tails to blunt ends before ligation. The goal is to efficiently join vector and insert DNA fragments for recombinant DNA construction.
Transgenic plants
Transgenic plants are plants that have been genetically modified using genetic engineering techniques to introduce new traits. The goal is to insert desirable genes from other organisms to produce crops with improved traits like pest or disease resistance, increased yield, or tolerance to environmental stresses. Some examples of transgenic crops include insect-resistant corn and cotton, herbicide-resistant soybeans, and golden rice which is enriched with vitamin A. While transgenic crops offer advantages to farmers and consumers, some concerns exist around their impact on human health, the environment, and traditional farming practices. Ongoing research continues to assess both the promises and risks of this emerging agricultural technology.
Marker free transgenic strategy
This presentation discusses strategies for developing transgenic plants without selectable marker genes. Marker genes are commonly used to identify transformed cells but can be problematic for public acceptance and future transformations. Methods described for producing marker-free transgenics include the MAT system which uses oncogenes for selection instead of antibiotics, site-specific recombination systems which flank the marker gene for later excision, and transposon-based systems which separate the gene of interest from the marker gene. While several viable methods exist, more work is still needed before marker-free crops can be commercialized. Removing marker genes supports multiple-gene stacking and improves public acceptance of transgenic technologies.
Screenable and Selectable Markers
Genetic manipulation of plant and animal cells have to be confirmed for further application. One such confirmatory method is the use of stains/dyes which produces fluorescence when the recombination is successful.
ENZYMES IN RECOMBINANT DNA TECHNOLOGY
DNA modifying enzymes play important roles in recombinant DNA technology. DNA polymerase synthesizes DNA from deoxyribonucleotides and is essential for DNA replication. It consists of subunits that carry out polymerase and exonuclease activities. Reverse transcriptase generates cDNA from an RNA template. Alkaline phosphatase, phosphatase, kinase and methyltransferases modify DNA through addition or removal of phosphate groups or methyl groups and are used in cloning experiments and DNA sequencing. Terminal transferase adds nucleotides to DNA ends. Restriction enzymes are inhibited by DNA methylation.
Genomic library
Genomic library and shotgun sequencing. It includes the topics about genomic library,construction method, its uses and applications, shotgun sequencing, difference between random and whole genome sequencing, its advantages and disadvantages etc.
Insect resisance ppt
1. The seminar discusses developing transgenic plants resistant to insects through the transfer of resistance genes from microorganisms, higher plants, and animals into crop plants.
2. Major objectives of plant biotechnology are to develop plants resistant to biotic and abiotic stresses. Resistance to insects has been achieved by introducing genes encoding Bt toxins from Bacillus thuringiensis and other insecticidal proteins.
3. Useful genes have been isolated from microbes like B. thuringiensis, higher plants like beans and tobacco, and animals like mammals. These genes have been successfully used to engineer insect-resistant crops like cotton, potato, tomato, and tobacco.
Gene transformation methods
Transformation is the process of altering an organism's genetic makeup by inserting new genes. Common transformation methods include Agrobacterium-mediated transformation, particle bombardment, protoplast transformation using polyethylene glycol or electroporation, and fibre-mediated DNA delivery. Agrobacterium transformation involves the bacteria transferring T-DNA from its Ti plasmid into the plant genome, while direct methods introduce naked DNA into plant cells using physical methods like particle bombardment or chemical treatments that make cell membranes permeable. Transformation allows improving crop traits like yield and stress resistance.
Organ culture- animal tissue culture
Organ culture involves maintaining small fragments of whole organs or tissues in culture media while retaining their three-dimensional structure and spatial distribution of cells. There are several methods of organ culture including culturing on plasma clots, agar, liquid media, or raft methods. Organ culture has various applications and allows studying cell interactions in a way that mimics the in vivo organ. It is currently being used to develop replacement organs and tissues for applications such as growing bladders, lungs, and heart patches. While progress is being made, developing fully functional human organs remains a challenge.
Transgenic plants ppt
Basic information about Transgenic plants, their need , process of making transgenics and use of transgenics
T dna & transposone tagging 1 (2)
Gene tagging uses recognizable DNA fragments like T-DNA or transposons to disrupt gene function and identify genes responsible for mutant phenotypes. T-DNA tagging in plants involves random integration of Agrobacterium T-DNA that can disrupt genes and create mutants. Transposon tagging relies on the ability of transposons to move within genomes and disrupt gene function. Both techniques have been used successfully to isolate numerous plant genes involved in traits like color and development.
Selectable marker genes
The document discusses selectable marker genes that are commonly used in plant transformation systems. Selectable marker genes are included in transformation vectors along with the target gene of interest. They confer resistance to transformed cells when grown on media containing toxic substances like antibiotics, herbicides, or antimetabolites. This allows transformed cells to survive while non-transformed cells die. There are three main categories of selectable marker genes: antibiotic resistance genes, antimetabolite marker genes, and herbicide resistance genes. Common examples of genes used include nptII for kanamycin resistance, pat/bar for phosphinothricin/glufosinate resistance, and epsps/aroA for glyphosate resistance.
ZINC FINGER NUCLEASE TECHNOLOGY
Zinc finger nucleases (ZFNs) allow for highly targeted editing of the genome. ZFNs consist of a DNA-binding domain made of zinc finger proteins and a DNA-cleaving domain. The ZFN pair binds to a target site and creates a double-strand break, which the cell repairs through non-homologous end joining or homologous recombination, enabling gene knockouts or targeted changes. ZFNs work in many cell types and animal models, providing a more efficient alternative to traditional transgenic techniques. They have applications in functional genomics, cell line engineering, and animal model generation.
Virus induced gene silencing
Virus-induced gene silencing (VIGS) is a technique that uses a viral vector carrying a fragment of a plant gene of interest to induce gene silencing. When the virus infects the plant, double-stranded RNA is produced from the viral genome and plant gene fragment, which is cleaved by the plant's dicer enzyme into siRNAs. These siRNAs are incorporated into the RISC complex and guide mRNA degradation of the targeted endogenous gene. Examples discussed were using tobacco rattle virus for VIGS in Nicotiana benthamiana and silencing tomato genes involved in the GABA pathway to study their roles in salt tolerance.
Chloroplast engineering
This document summarizes research on chloroplast engineering for various applications. Chloroplasts naturally contain their own DNA and can be genetically engineered via homologous recombination. This allows for high levels of transgene expression without gene silencing effects. The document discusses how chloroplasts have been engineered for herbicide resistance, pathogen resistance, drought tolerance, and production of recombinant proteins. While chloroplast engineering holds promise, limitations include lack of expression in non-green cells and full genome sequence information for some species.
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Antisense RNA technology
anti sense RNA technology is one the method for gene silencing. it found very effective making Flavr savr tomato. hope this ppt will help you.
Regulation of gene expression.pdf
Regulation of gene expression.
It can be helpful for the students of Biotechnology, Genetics, Molecular Biology, Microbiology and othe Biology related courses.
If you've got any queries, you can directly mail me to pratimasingdan@gmail.com.
I hope this will help you a lot.
ONLY THE LAST QUESTION IS THE POINT OF POST. THE OTHER PAGES ARE B.pdf
ONLY THE LAST QUESTION IS THE POINT OF POST. THE OTHER PAGES ARE
BACKGROUND CONTEXT Lab: Differential Expression Differential gene expression provides
the ability for a cell or organism to respond to a constantly changing external environment. The
specific constellation of proteins required for optimal function and growth varies with cellular
age and environmental context. Thus, protein production is carefully regulated by multiple
mechanisms that modulate both transcriptional and translational pathways. Control of
transcription initiation by RNA polymerase is a predominant mechanism for regulating
expression of specific proteins, presumably because it provides maximal conservation of energy
for the cell. We can often observe the consequence of differential transcription due to the
presence or absence of particular proteins or the growth in particular environments. Control can
also occur at translation; the mRNA is synthesized, but only in certain circumstances is it
translated. Control can also occur at the level of protein function; the protein is inactive, or
activity is not observed due to the lack of the substrate. In this lab we will observe differential
expression of two different genes encoded on plasmids. We will analyze transcriptional activity,
translational activity, and protein function. Plasmids are extra-chromosomal DNA. Bacteria often
have plasmids and will replicate the plasmid and pass it to daughter cells (vertical transmission)
and to neighboring cells (horizontal). Plasmids are a mechanism of gene diversity. In order to
stably retain the plasmid, there needs to be some type of metabolic reason for the bacteria to
maintain the plasmid. In other words, the plasmid confers an advantage. Plasmids contain: 1. Ori:
the plasmid may present is low or high copy number. 2. Lab generated plasmids typically also
contain a selectable marker (antibiotic resistance), 3. Additional gene for ease of visual screening
4. Multiple cloning site
pUC19 is one of a series of plasmid cloning vectors created by Joachim Messing and co-workers.
The designation "pUC" is derived from the classical "p" prefix (denoting "plasmid") and the
abbreviation for the University of California, where early work on the plasmid series had been
conducted. It is a circular double stranded DNA and has 2686 base pairs. pUC19 is one of the
most widely used vector molecules as the recombinants, or the cells into which foreign DNA has
been introduced, can be easily distinguished from the non-recombinants based on color
differences of colonies on growth media. pUC18 is similar to pUC19, but the MCS region is
reversed. - pUC 19 has an origin of replication and is maintained at a high copy number. -
pUC19 encodes for an ampicillin resistance gene (amopR), via a -lactamase enzyme that
functions by degrading ampicillin and reducing its toxicity to the host. - It has an N-terminal
fragment of -galactosidase (lacZ) gene of E. coli which allows for visual screening of
recombinant.
ONLY THE LAST QUESTION IS THE POINT OF POST. THE OTHER PAGES ARE BAC.pdf
ONLY THE LAST QUESTION IS THE POINT OF POST. THE OTHER PAGES ARE
BACKGROUND CONTEXT Lab: Differential Expression Differential gene expression provides
the ability for a cell or organism to respond to a constantly changing external environment. The
specific constellation of proteins required for optimal function and growth varies with cellular
age and environmental context. Thus, protein production is carefully regulated by multiple
mechanisms that modulate both transcriptional and translational pathways. Control of
transcription initiation by RNA polymerase is a predominant mechanism for regulating
expression of specific proteins, presumably because it provides maximal conservation of energy
for the cell. We can often observe the consequence of differential transcription due to the
presence or absence of particular proteins or the growth in particular environments. Control can
also occur at translation; the mRNA is synthesized, but only in certain circumstances is it
translated. Control can also occur at the level of protein function; the protein is inactive, or
activity is not observed due to the lack of the substrate. In this lab we will observe differential
expression of two different genes encoded on plasmids. We will analyze transcriptional activity,
translational activity, and protein function. Plasmids are extra-chromosomal DNA. Bacteria often
have plasmids and will replicate the plasmid and pass it to daughter cells (vertical transmission)
and to neighboring cells (horizontal). Plasmids are a mechanism of gene diversity. In order to
stably retain the plasmid, there needs to be some type of metabolic reason for the bacteria to
maintain the plasmid. In other words, the plasmid confers an advantage. Plasmids contain: 1. Ori:
the plasmid may present is low or high copy number. 2. Lab generated plasmids typically also
contain a selectable marker (antibiotic resistance), 3. Additional gene for ease of visual screening
4. Multiple cloning site
pUC19 is one of a series of plasmid cloning vectors created by Joachim Messing and co-workers.
The designation "pUC" is derived from the classical "p" prefix (denoting "plasmid") and the
abbreviation for the University of California, where early work on the plasmid series had been
conducted. It is a circular double stranded DNA and has 2686 base pairs. pUC19 is one of the
most widely used vector molecules as the recombinants, or the cells into which foreign DNA has
been introduced, can be easily distinguished from the non-recombinants based on color
differences of colonies on growth media. pUC18 is similar to pUC19, but the MCS region is
reversed. - pUC 19 has an origin of replication and is maintained at a high copy number. -
pUC19 encodes for an ampicillin resistance gene (amopR), via a -lactamase enzyme that
functions by degrading ampicillin and reducing its toxicity to the host. - It has an N-terminal
fragment of -galactosidase (lacZ) gene of E. coli which allows for visual screening of
recombinant.
Lab Differential Expression Differential gene expression provides th.pdf
Lab: Differential Expression Differential gene expression provides the ability for a cell or
organism to respond to a constantly changing external environment. The specific constellation of
proteins required for optimal function and growth varies with cellular age and environmental
context. Thus, protein production is carefully regulated by multiple mechanisms that modulate
both transcriptional and translational pathways. Control of transcription initiation by RNA
polymerase is a predominant mechanism for regulating expression of specific proteins,
presumably because it provides maximal conservation of energy for the cell. We can often
observe the consequence of differential transcription due to the presence or absence of particular
proteins or the growth in particular environments. Control can also occur at translation; the
mRNA is synthesized, but only in certain circumstances is it translated. Control can also occur at
the level of protein function; the protein is inactive, or activity is not observed due to the lack of
the substrate. In this lab we will observe differential expression of two different genes encoded
on plasmids. We will analyze transcriptional activity, translational activity, and protein function.
Plasmids are extra-chromosomal DNA. Bacteria often have plasmids and will replicate the
plasmid and pass it to daughter cells (vertical transmission) and to neighboring cells (horizontal).
Plasmids are a mechanism of gene diversity. In order to stably retain the plasmid, there needs to
be some type of metabolic reason for the bacteria to maintain the plasmid. In other words, the
plasmid confers an advantage. Plasmids contain: 1. Ori: the plasmid may present is low or high
copy number. 2. Lab generated plasmids typically also contain a selectable marker (antibiotic
resistance), 3. Additional gene for ease of visual screening 4. Multiple cloning site
pUC19 is one of a series of plasmid cloning vectors created by Joachim Messing and co-workers.
The designation "pUC" is derived from the classical "p" prefix (denoting "plasmid") and the
abbreviation for the University of California, where early work on the plasmid series had been
conducted. It is a circular double stranded DNA and has 2686 base pairs. pUC19 is one of the
most widely used vector molecules as the recombinants, or the cells into which foreign DNA has
been introduced, can be easily distinguished from the non-recombinants based on color
differences of colonies on growth media. pUC18 is similar to pUC19, but the MCS region is
reversed. - pUC 19 has an origin of replication and is maintained at a high copy number. -
pUC19 encodes for an ampicillin resistance gene (amopR), via a -lactamase enzyme that
functions by degrading ampicillin and reducing its toxicity to the host. - It has an N-terminal
fragment of -galactosidase (lacZ) gene of E. coli which allows for visual screening of
recombinant plasmids. The transformed cells containing the plasmid with the gene of interest ca.
Lab Differential Expression Differential gene expression provides .pdf
Lab: Differential Expression Differential gene expression provides the ability for a cell or
organism to respond to a constantly changing external environment. The specific constellation of
proteins required for optimal function and growth varies with cellular age and environmental
context. Thus, protein production is carefully regulated by multiple mechanisms that modulate
both transcriptional and translational pathways. Control of transcription initiation by RNA
polymerase is a predominant mechanism for regulating expression of specific proteins,
presumably because it provides maximal conservation of energy for the cell. We can often
observe the consequence of differential transcription due to the presence or absence of particular
proteins or the growth in particular environments. Control can also occur at translation; the
mRNA is synthesized, but only in certain circumstances is it translated. Control can also occur at
the level of protein function; the protein is inactive, or activity is not observed due to the lack of
the substrate. In this lab we will observe differential expression of two different genes encoded
on plasmids. We will analyze transcriptional activity, translational activity, and protein function.
Plasmids are extra-chromosomal DNA. Bacteria often have plasmids and will replicate the
plasmid and pass it to daughter cells (vertical transmission) and to neighboring cells (horizontal).
Plasmids are a mechanism of gene diversity. In order to stably retain the plasmid, there needs to
be some type of metabolic reason for the bacteria to maintain the plasmid. In other words, the
plasmid confers an advantage. Plasmids contain: 1. Ori: the plasmid may present is low or high
copy number. 2. Lab generated plasmids typically also contain a selectable marker (antibiotic
resistance), 3. Additional gene for ease of visual screening 4. Multiple cloning site
pUC19 is one of a series of plasmid cloning vectors created by Joachim Messing and co-workers.
The designation "pUC" is derived from the classical "p" prefix (denoting "plasmid") and the
abbreviation for the University of California, where early work on the plasmid series had been
conducted. It is a circular double stranded DNA and has 2686 base pairs. pUC19 is one of the
most widely used vector molecules as the recombinants, or the cells into which foreign DNA has
been introduced, can be easily distinguished from the non-recombinants based on color
differences of colonies on growth media. pUC18 is similar to pUC19, but the MCS region is
reversed. - pUC 19 has an origin of replication and is maintained at a high copy number. -
pUC19 encodes for an ampicillin resistance gene (amopR), via a -lactamase enzyme that
functions by degrading ampicillin and reducing its toxicity to the host. - It has an N-terminal
fragment of -galactosidase (lacZ) gene of E. coli which allows for visual screening of
recombinant plasmids. The transformed cells containing the plasmid with the gene of interest ca.
Antisense RNA Technology Forr Crop Improvement
Antisense RNA Technology Forr Crop ImprovementJunagadh Agricultural University, Junagadh (Guj.), India
Researchers used RNA interference technology to genetically modify maize kernels for improved nutritional value. They targeted the lysine catabolism pathway by suppressing the LKR/SDH genes through recombinant RNAi. This led to transgenic maize with higher free lysine content. Experiments showed segregated reduction of LKR/SDH expression in mature F1 kernels, with consistent reduction at later developmental stages but normal accumulation earlier. Quantitative analysis confirmed LKR/SDH reduction in both embryo and endosperm, along with decreased LKR activity and increased free lysine and saccharopine levels. The study demonstrated that RNAi can effectively modify lysine metabolism in maize to enhance its nutritional profile.Â
Gene Silencing
This document discusses gene silencing, which is the suppression or interruption of gene expression at the transcriptional or translational level. It regulates gene expression and prevents certain genes from being expressed. There are several types of gene silencing, including transcriptional silencing through genomic imprinting, paramutation, and transposon silencing. Post-transcriptional gene silencing occurs through RNA interference pathways using small interfering RNA, microRNA, Dicer, and RISC complex. Research methods for gene silencing include antisense oligonucleotides, ribozymes, siRNA, and microRNA. Gene silencing has applications in biotechnology and medicine, with advantages such as being cost effective and having high specificity, though it also has disadvantages like potential toxicity.
Antisense RNA technology & its role in crop improvement ppt surendra singh
This document discusses antisense RNA technology and its role in crop improvement. It begins by introducing antisense RNA as a method for inhibiting gene expression through complementary base pairing. It then discusses various applications of antisense RNA technology in crop improvement, including delaying fruit ripening in tomato and flower senescence in carnation, producing male sterility in petunia, and reducing neurotoxins in crops like khesari. The document concludes by noting that antisense RNA technology is an efficient gene knockdown method that could be useful for genetic improvement in many plant species.
Transgene silencing
Gene silencing, also known as RNA interference, is a natural process in plants that evolved as a defense mechanism against viruses. Transgene silencing occurs when introduced transgenes are not expressed due to this silencing process. The first evidence of this was discovered in 1990 by R. Jorgensen in petunia plants, where both an introduced gene and endogenous gene were silenced. Gene silencing can occur at the transcriptional or post-transcriptional level through mechanisms like siRNA and microRNA production. Virus-induced gene silencing is a technique used to study gene function and develop virus-resistant plants by suppressing viral gene expression. Applications of gene silencing include developing disease-resistant crops and modifying plant traits.
Gene expression & its regulation.
This presentation provide knowledge about Gene Expression & its regulation in brief.
i hope it gives some information about gene expression in your academic time.
In this presentation mentioned - Lac Operon and its expressor.
EPIGENETIC.pptx
Gene silencing is a technique that reduces or eliminates the production of a protein from its corresponding gene through mechanisms other than genetic modification. There are two main types of gene silencing - transcriptional and post-transcriptional. Post-transcriptional gene silencing includes RNA interference (RNAi), which involves introducing double-stranded RNA that binds to mRNA and prevents replication, effectively silencing gene expression in a sequence-specific manner. RNAi is a powerful tool for gene function analysis and applications in biotechnology and agriculture.
Transcriptional and post transcriptional regulation of gene expression
Gene expression is regulated at the transcriptional and post-transcriptional levels. Transcriptional regulation involves proteins binding to promoter and enhancer sequences to control RNA polymerase recruitment and initiation of transcription. Eukaryotic gene expression requires transcription factors, coactivators, and basal transcription factors to assemble the transcription initiation complex. Post-transcriptional regulation influences RNA processing, transport, translation, and degradation.
Control of gene expression ppt
Control of gene expression ppt
definition of gene expression
inducible gene expression
repressible gene expression
control of gene expression in eukaryotics .all the in information about this topic is include .
Gene silencing
Gene silencing is a technique that reduces or eliminates protein production from a gene. It occurs through RNA interference, where small interfering RNAs are processed by an enzyme called Dicer and loaded into an RNA-induced silencing complex (RISC) that targets complementary mRNAs for degradation. There are two main types of gene silencing - transcriptional which alters DNA accessibility, and post-transcriptional via RNAi technologies. RNAi has therapeutic applications for cancer, infectious diseases, and neurodegenerative disorders by knocking down target genes. The first approved RNAi drug, Patisiran, treats hereditary transthyretin-mediated amyloidosis.
molecular.pdf
1. Operon refers to a cluster of structural genes regulated by a common operator and involved in the same metabolic pathway. Examples include the lac and tryptophan operons.
2. Signal transduction is the process by which extracellular signals are converted into intracellular responses, involving the steps of reception, transduction, and response.
3. Cloning involves making identical copies of a gene, which can be the original or a mutated version, using DNA ligase and restriction endonucleases.
Regulation of Gene expression
The document discusses regulation of gene expression. It describes how gene expression involves transcription of DNA into mRNA which is then translated into proteins. Regulation of gene expression is important for organisms to adapt to their environment and involves mechanisms like transcription control, RNA processing, translation control and protein modification. Key examples discussed are the lac operon and lambda phage switch which demonstrate transcriptional regulation through repressor and activator proteins. The role of epigenetic factors like DNA and histone methylation and acetylation in long-term stable regulation of gene expression is also summarized.
Antisense RNA in crop
This document summarizes a seminar presentation on antisense RNA technology. The presentation covered:
1. The introduction defined antisense RNA and its potential for crop improvement to meet rising global food demand.
2. The mechanisms of antisense RNA technology were explained, including how antisense RNA binds to mRNA to inhibit translation and activate RNase H degradation.
3. The history of antisense technology was discussed, including its first observation in nature's HOK/SOK system and early experiments in the 1990s that helped define gene silencing.
Transcriptional repressors ppt Repressor proteins involved in transcription
This document summarizes transcriptional repressor proteins. It discusses how repressors inhibit gene expression by binding to DNA or RNA. There are two main types of repressors - DNA-binding repressors that block RNA polymerase attachment, and RNA-binding repressors that prevent protein translation. Repressors can be passive and compete for binding sites, or active with intrinsic repression activity targeting chromatin. Examples given are the lac and trp operon repressors in prokaryotes. Co-repressors are discussed as molecules that bind and activate repressor function.
Molecular mechanism of antisense molecules
Antisense RNA is a single-stranded RNA that is complementary to messenger RNA (mRNA) and inhibits its translation. Historically, antisense RNA effects were confused with RNA interference, which involves small interfering RNAs targeting mRNA for degradation. Antisense RNA works by forming duplexes with mRNA, blocking the ribosome from accessing nucleotides or leading to degradation. Examples include transgenic Flavr Savr tomatoes with reduced ethylene production using antisense RNA against an ethylene-producing enzyme, and natural antisense RNA in mice and humans that blocks insulin-like growth factor 2 receptor mRNA. While promising, antisense RNA drugs still face challenges in design, activity, and delivery that have limited
Similar to Antisense rna technology (20)
ONLY THE LAST QUESTION IS THE POINT OF POST. THE OTHER PAGES ARE B.pdf
ONLY THE LAST QUESTION IS THE POINT OF POST. THE OTHER PAGES ARE B.pdf
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ONLY THE LAST QUESTION IS THE POINT OF POST. THE OTHER PAGES ARE BAC.pdf
ONLY THE LAST QUESTION IS THE POINT OF POST. THE OTHER PAGES ARE BAC.pdf
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Lab Differential Expression Differential gene expression provides th.pdf
Lab Differential Expression Differential gene expression provides th.pdf
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Lab Differential Expression Differential gene expression provides .pdf
Lab Differential Expression Differential gene expression provides .pdf
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Antisense RNA technology & its role in crop improvement ppt surendra singh
Antisense RNA technology & its role in crop improvement ppt surendra singh
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Transcriptional and post transcriptional regulation of gene expression
Transcriptional and post transcriptional regulation of gene expression
Â
Transcriptional repressors ppt Repressor proteins involved in transcription
Transcriptional repressors ppt Repressor proteins involved in transcription
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Recently uploaded
Discovery of An Apparent Red, High-Velocity Type Ia Supernova at đł = 2.9 wi...
We present the JWST discovery of SNâ2023adsy, a transient object located in a host galaxy JADES-GS
+
53.13485
â
27.82088
with a host spectroscopic redshift of
2.903
±
0.007
. The transient was identified in deep James Webb Space Telescope (JWST)/NIRCam imaging from the JWST Advanced Deep Extragalactic Survey (JADES) program. Photometric and spectroscopic followup with NIRCam and NIRSpec, respectively, confirm the redshift and yield UV-NIR light-curve, NIR color, and spectroscopic information all consistent with a Type Ia classification. Despite its classification as a likely SNâIa, SNâ2023adsy is both fairly red (
ïżœ
âą
(
ïżœ
â
ïżœ
)
âŒ
0.9
) despite a host galaxy with low-extinction and has a high CaâII velocity (
19
,
000
±
2
,
000
km/s) compared to the general population of SNeâIa. While these characteristics are consistent with some Ca-rich SNeâIa, particularly SNâ2016hnk, SNâ2023adsy is intrinsically brighter than the low-
ïżœ
Ca-rich population. Although such an object is too red for any low-
ïżœ
cosmological sample, we apply a fiducial standardization approach to SNâ2023adsy and find that the SNâ2023adsy luminosity distance measurement is in excellent agreement (
âČ
1
âą
ïżœ
) with
Î
CDM. Therefore unlike low-
ïżœ
Ca-rich SNeâIa, SNâ2023adsy is standardizable and gives no indication that SNâIa standardized luminosities change significantly with redshift. A larger sample of distant SNeâIa is required to determine if SNâIa population characteristics at high-
ïżœ
truly diverge from their low-
ïżœ
counterparts, and to confirm that standardized luminosities nevertheless remain constant with redshift.
The cost of acquiring information by natural selection
This is a short talk that I gave at the Banff International Research Station workshop on Modeling and Theory in Population Biology. The idea is to try to understand how the burden of natural selection relates to the amount of information that selection puts into the genome.
It's based on the first part of this research paper:
The cost of information acquisition by natural selection
Ryan Seamus McGee, Olivia Kosterlitz, Artem Kaznatcheev, Benjamin Kerr, Carl T. Bergstrom
bioRxiv 2022.07.02.498577; doi: https://doi.org/10.1101/2022.07.02.498577
Gadgets for management of stored product pests_Dr.UPR.pdf
Insectsplayamajorroleinthedeteriorationoffoodgrainscausingbothquantitativeandqualitativelosses
ïWellprovedthatnogranariescanbefilledwithgrainswithoutinsectsastheharvestedproducecontainegg(or)larvae(or)pupae(or)adultinsectinthembecauseoffieldcarryoverinfestationwhichcannotbeavoidedindevelopingcountrieslikeIndia
ïSimpletechnologiesfortimelydetectionofinsectsinthestoredproduceandtherebyplantimelycontrolmeasures
Summary Of transcription and Translation.pdf
Hello Everyone Here We are Sharing You with The process of protien Synthesis in very short points you will be Able to understand It Very well
Travis Hills of MN is Making Clean Water Accessible to All Through High Flux ...
By harnessing the power of High Flux Vacuum Membrane Distillation, Travis Hills from MN envisions a future where clean and safe drinking water is accessible to all, regardless of geographical location or economic status.
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
Context. With a mass exceeding several 104 Mâ and a rich and dense population of massive stars, supermassive young star clusters
represent the most massive star-forming environment that is dominated by the feedback from massive stars and gravitational interactions
among stars.
Aims. In this paper we present the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS) project, which aims to investigate
the influence of the starburst environment on the formation of stars and planets, and on the evolution of both low and high mass stars.
The primary targets of this project are Westerlund 1 and 2, the closest supermassive star clusters to the Sun.
Methods. The project is based primarily on recent observations conducted with the Chandra and JWST observatories. Specifically,
the Chandra survey of Westerlund 1 consists of 36 new ACIS-I observations, nearly co-pointed, for a total exposure time of 1 Msec.
Additionally, we included 8 archival Chandra/ACIS-S observations. This paper presents the resulting catalog of X-ray sources within
and around Westerlund 1. Sources were detected by combining various existing methods, and photon extraction and source validation
were carried out using the ACIS-Extract software.
Results. The EWOCS X-ray catalog comprises 5963 validated sources out of the 9420 initially provided to ACIS-Extract, reaching a
photon flux threshold of approximately 2 Ă 10â8 photons cmâ2
s
â1
. The X-ray sources exhibit a highly concentrated spatial distribution,
with 1075 sources located within the central 1 arcmin. We have successfully detected X-ray emissions from 126 out of the 166 known
massive stars of the cluster, and we have collected over 71 000 photons from the magnetar CXO J164710.20-455217.
Evidence of Jet Activity from the Secondary Black Hole in the OJ 287 Binary S...
Wereport the study of a huge optical intraday flare on 2021 November 12 at 2 a.m. UT in the blazar OJ287. In the binary black hole model, it is associated with an impact of the secondary black hole on the accretion disk of the primary. Our multifrequency observing campaign was set up to search for such a signature of the impact based on a prediction made 8 yr earlier. The first I-band results of the flare have already been reported by Kishore et al. (2024). Here we combine these data with our monitoring in the R-band. There is a big change in the RâI spectral index by 1.0 ±0.1 between the normal background and the flare, suggesting a new component of radiation. The polarization variation during the rise of the flare suggests the same. The limits on the source size place it most reasonably in the jet of the secondary BH. We then ask why we have not seen this phenomenon before. We show that OJ287 was never before observed with sufficient sensitivity on the night when the flare should have happened according to the binary model. We also study the probability that this flare is just an oversized example of intraday variability using the Krakow data set of intense monitoring between 2015 and 2023. We find that the occurrence of a flare of this size and rapidity is unlikely. In machine-readable Tables 1 and 2, we give the full orbit-linked historical light curve of OJ287 as well as the dense monitoring sample of Krakow.
Alternate Wetting and Drying - Climate Smart Agriculture
Alternate Wetting and Drying - Climate Smart AgricultureInternational Food Policy Research Institute- South Asia Office
PPT on Alternate Wetting and Drying presented at the three-day 'Training and Validation Workshop on Modules of Climate Smart Agriculture (CSA) Technologies in South Asia' workshop on April 22, 2024. Â
Methods of grain storage Structures in India.pdf
âąPost-harvestlossesaccountforabout10%oftotalfoodgrainsduetounscientificstorage,insects,rodents,micro-organismsetc.,
âąTotalfoodgrainproductioninindiais311milliontonnesandstorageis145mt.InIndia,annualstoragelosseshavebeenestimated14mtworthofRs.7,000croreinwhichinsectsaloneaccountfornearlyRs.1,300crores.
âąInIndiaoutofthetotalproduction,about30%ismarketablesurplus
âąRemaining70%isretainedandstoredbyfarmersforconsumption,seed,feed.Hence,growerneedstoragefacilitytoholdaportionofproducetosellwhenthemarketingpriceisfavourable
âąTradersandCo-operativesatmarketcentresneedstoragestructurestoholdgrainswhenthetransportfacilityisinadequate
Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...
Context. The observation of several L-band emission sources in the S cluster has led to a rich discussion of their nature. However, a definitive answer to the classification of the dusty objects requires an explanation for the detection of compact Doppler-shifted BrÎł emission. The ionized hydrogen in combination with the observation of mid-infrared L-band continuum emission suggests that most of these sources are embedded in a dusty envelope. These embedded sources are part of the S-cluster, and their relationship to the S-stars is still under debate. To date, the question of the origin of these two populations has been vague, although all explanations favor migration processes for the individual cluster members. Aims. This work revisits the S-cluster and its dusty members orbiting the supermassive black hole SgrA* on bound Keplerian orbits from a kinematic perspective. The aim is to explore the Keplerian parameters for patterns that might imply a nonrandom distribution of the sample. Additionally, various analytical aspects are considered to address the nature of the dusty sources. Methods. Based on the photometric analysis, we estimated the individual HâK and KâL colors for the source sample and compared the results to known cluster members. The classification revealed a noticeable contrast between the S-stars and the dusty sources. To fit the flux-density distribution, we utilized the radiative transfer code HYPERION and implemented a young stellar object Class I model. We obtained the position angle from the Keplerian fit results; additionally, we analyzed the distribution of the inclinations and the longitudes of the ascending node. Results. The colors of the dusty sources suggest a stellar nature consistent with the spectral energy distribution in the near and midinfrared domains. Furthermore, the evaporation timescales of dusty and gaseous clumps in the vicinity of SgrA* are much shorter ( 2yr) than the epochs covered by the observations (â15yr). In addition to the strong evidence for the stellar classification of the D-sources, we also find a clear disk-like pattern following the arrangements of S-stars proposed in the literature. Furthermore, we find a global intrinsic inclination for all dusty sources of 60 ± 20âŠ, implying a common formation process. Conclusions. The pattern of the dusty sources manifested in the distribution of the position angles, inclinations, and longitudes of the ascending node strongly suggests two different scenarios: the main-sequence stars and the dusty stellar S-cluster sources share a common formation history or migrated with a similar formation channel in the vicinity of SgrA*. Alternatively, the gravitational influence of SgrA* in combination with a massive perturber, such as a putative intermediate mass black hole in the IRS 13 cluster, forces the dusty objects and S-stars to follow a particular orbital arrangement. Key words. stars: black holesâ stars: formationâ Galaxy: centerâ galaxies: star formation
ESA/ACT Science Coffee: Diego Blas - Gravitational wave detection with orbita...
ESA/ACT Science Coffee: Diego Blas - Gravitational wave detection with orbita...Advanced-Concepts-Team
Presentation in the Science Coffee of the Advanced Concepts Team of the European Space Agency on the 07.06.2024.
Speaker: Diego Blas (IFAE/ICREA)
Title: Gravitational wave detection with orbital motion of Moon and artificial
Abstract:
In this talk I will describe some recent ideas to find gravitational waves from supermassive black holes or of primordial origin by studying their secular effect on the orbital motion of the Moon or satellites that are laser ranged.Â
Describing and Interpreting an Immersive Learning Case with the Immersion Cub...
Current descriptions of immersive learning cases are often difficult or impossible to compare. This is due to a myriad of different options on what details to include, which aspects are relevant, and on the descriptive approaches employed. Also, these aspects often combine very specific details with more general guidelines or indicate intents and rationales without clarifying their implementation. In this paper we provide a method to describe immersive learning cases that is structured to enable comparisons, yet flexible enough to allow researchers and practitioners to decide which aspects to include. This method leverages a taxonomy that classifies educational aspects at three levels (uses, practices, and strategies) and then utilizes two frameworks, the Immersive Learning Brain and the Immersion Cube, to enable a structured description and interpretation of immersive learning cases. The method is then demonstrated on a published immersive learning case on training for wind turbine maintenance using virtual reality. Applying the method results in a structured artifact, the Immersive Learning Case Sheet, that tags the case with its proximal uses, practices, and strategies, and refines the free text case description to ensure that matching details are included. This contribution is thus a case description method in support of future comparative research of immersive learning cases. We then discuss how the resulting description and interpretation can be leveraged to change immersion learning cases, by enriching them (considering low-effort changes or additions) or innovating (exploring more challenging avenues of transformation). The method holds significant promise to support better-grounded research in immersive learning.
Anti-Universe And Emergent Gravity and the Dark Universe
Recent theoretical progress indicates that spacetime and gravity emerge together from the entanglement structure of an underlying microscopic theory. These ideas are best understood in Anti-de Sitter space, where they rely on the area law for entanglement entropy. The extension to de Sitter space requires taking into account the entropy and temperature associated with the cosmological horizon. Using insights from string theory, black hole physics and quantum information theory we argue that the positive dark energy leads to a thermal volume law contribution to the entropy that overtakes the area law precisely at the cosmological horizon. Due to the competition between area and volume law entanglement the microscopic de Sitter states do not thermalise at sub-Hubble scales: they exhibit memory effects in the form of an entropy displacement caused by matter. The emergent laws of gravity contain an additional âdarkâ gravitational force describing the âelasticâ response due to the entropy displacement. We derive an estimate of the strength of this extra force in terms of the baryonic mass, Newtonâs constant and the Hubble acceleration scale a0 = cH0, and provide evidence for the fact that this additional âdark gravity forceâ explains the observed phenomena in galaxies and clusters currently attributed to dark matter.
JAMES WEBB STUDY THE MASSIVE BLACK HOLE SEEDS
The pathway(s) to seeding the massive black holes (MBHs) that exist at the heart of galaxies in the present and distant Universe remains an unsolved problem. Here we categorise, describe and quantitatively discuss the formation pathways of both light and heavy seeds. We emphasise that the most recent computational models suggest that rather than a bimodal-like mass spectrum between light and heavy seeds with light at one end and heavy at the other that instead a continuum exists. Light seeds being more ubiquitous and the heavier seeds becoming less and less abundant due the rarer environmental conditions required for their formation. We therefore examine the different mechanisms that give rise to different seed mass spectrums. We show how and why the mechanisms that produce the heaviest seeds are also among the rarest events in the Universe and are hence extremely unlikely to be the seeds for the vast majority of the MBH population. We quantify, within the limits of the current large uncertainties in the seeding processes, the expected number densities of the seed mass spectrum. We argue that light seeds must be at least 103 to 105 times more numerous than heavy seeds to explain the MBH population as a whole. Based on our current understanding of the seed population this makes heavy seeds (Mseed > 103 Mâ) a significantly more likely pathway given that heavy seeds have an abundance pattern than is close to and likely in excess of 10â4 compared to light seeds. Finally, we examine the current state-of-the-art in numerical calculations and recent observations and plot a path forward for near-future advances in both domains.
MICROBIAL INTERACTION PPT/ MICROBIAL INTERACTION AND THEIR TYPES // PLANT MIC...
MICROBIAL INTERACTION PPT/ MICROBIAL INTERACTION AND THEIR TYPES // PLANT MIC...ABHISHEK SONI NIMT INSTITUTE OF MEDICAL AND PARAMEDCIAL SCIENCES , GOVT PG COLLEGE NOIDA
Microbial interaction
Microorganisms interacts with each other and can be physically associated with another organisms in a variety of ways.
One organism can be located on the surface of another organism as an ectobiont or located within another organism as endobiont.
Microbial interaction may be positive such as mutualism, proto-cooperation, commensalism or may be negative such as parasitism, predation or competition
Types of microbial interaction
Positive interaction: mutualism, proto-cooperation, commensalism
Negative interaction: Ammensalism (antagonism), parasitism, predation, competition
I. Mutualism:
It is defined as the relationship in which each organism in interaction gets benefits from association. It is an obligatory relationship in which mutualist and host are metabolically dependent on each other.
Mutualistic relationship is very specific where one member of association cannot be replaced by another species.
Mutualism require close physical contact between interacting organisms.
Relationship of mutualism allows organisms to exist in habitat that could not occupied by either species alone.
Mutualistic relationship between organisms allows them to act as a single organism.
Examples of mutualism:
i. Lichens:
Lichens are excellent example of mutualism.
They are the association of specific fungi and certain genus of algae. In lichen, fungal partner is called mycobiont and algal partner is called
II. Syntrophism:
It is an association in which the growth of one organism either depends on or improved by the substrate provided by another organism.
In syntrophism both organism in association gets benefits.
Compound A
Utilized by population 1
Compound B
Utilized by population 2
Compound C
utilized by both Population 1+2
Products
In this theoretical example of syntrophism, population 1 is able to utilize and metabolize compound A, forming compound B but cannot metabolize beyond compound B without co-operation of population 2. Population 2is unable to utilize compound A but it can metabolize compound B forming compound C. Then both population 1 and 2 are able to carry out metabolic reaction which leads to formation of end product that neither population could produce alone.
Examples of syntrophism:
i. Methanogenic ecosystem in sludge digester
Methane produced by methanogenic bacteria depends upon interspecies hydrogen transfer by other fermentative bacteria.
Anaerobic fermentative bacteria generate CO2 and H2 utilizing carbohydrates which is then utilized by methanogenic bacteria (Methanobacter) to produce methane.
ii. Lactobacillus arobinosus and Enterococcus faecalis:
In the minimal media, Lactobacillus arobinosus and Enterococcus faecalis are able to grow together but not alone.
The synergistic relationship between E. faecalis and L. arobinosus occurs in which E. faecalis require folic acid
Â
Immersive Learning That Works: Research Grounding and Paths Forward
We will metaverse into the essence of immersive learning, into its three dimensions and conceptual models. This approach encompasses elements from teaching methodologies to social involvement, through organizational concerns and technologies. Challenging the perception of learning as knowledge transfer, we introduce a 'Uses, Practices & Strategies' model operationalized by the 'Immersive Learning Brain' and âImmersion Cubeâ frameworks. This approach offers a comprehensive guide through the intricacies of immersive educational experiences and spotlighting research frontiers, along the immersion dimensions of system, narrative, and agency. Our discourse extends to stakeholders beyond the academic sphere, addressing the interests of technologists, instructional designers, and policymakers. We span various contexts, from formal education to organizational transformation to the new horizon of an AI-pervasive society. This keynote aims to unite the iLRN community in a collaborative journey towards a future where immersive learning research and practice coalesce, paving the way for innovative educational research and practice landscapes.
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Â
The cost of acquiring information by natural selection
The cost of acquiring information by natural selection
Â
Gadgets for management of stored product pests_Dr.UPR.pdf
Gadgets for management of stored product pests_Dr.UPR.pdf
Â
Travis Hills of MN is Making Clean Water Accessible to All Through High Flux ...
Travis Hills of MN is Making Clean Water Accessible to All Through High Flux ...
Â
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
Â
Evidence of Jet Activity from the Secondary Black Hole in the OJ 287 Binary S...
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Â
Alternate Wetting and Drying - Climate Smart Agriculture
Alternate Wetting and Drying - Climate Smart Agriculture
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Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...
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Juaristi, Jon. - El canon espanol. El legado de la cultura española a la civi...
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Describing and Interpreting an Immersive Learning Case with the Immersion Cub...
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Anti-Universe And Emergent Gravity and the Dark Universe
Anti-Universe And Emergent Gravity and the Dark Universe
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MICROBIAL INTERACTION PPT/ MICROBIAL INTERACTION AND THEIR TYPES // PLANT MIC...
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Immersive Learning That Works: Research Grounding and Paths Forward
Immersive Learning That Works: Research Grounding and Paths Forward
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Antisense rna technology
- 2. INTRODUCTION ï¶ Antisense RNA is a single standard RNA that is complementary to a protein coding messenger RNA (mRNA) with which it hybridizes , and thereby blocks its translation into protein. ï¶ Example : hok /sok system of the E.coli R1 plasmid. ï¶This translational arrest causes reduced amount of protein expression. ï¶Well-known examples of GM plants produced by this technology â ï¶ the Flavr savr tomato ï¶ Two cultivars of ring spot â resistant papaya. HISTORY: ï¶ Antisense effect first demonstrated by Zemen nick & Stephenson in 1970 on âRous sarcoma virusâ . ï¶First time antisense oligonucleotides are synthesized by Eckstein and colleagues.
- 4. NATUREâS ANTISENSE SYSTEM ï¶ There is HOK (host killing)/ SOK (suppress killing) system in R1 plasmid in E.coli. ï¶ when E.coli cell undergoes division ,daughter cell inherit hok gene & sok gene from parent . But due to short life of cell , the sok gene is get degraded. So in normal cell , hok gene get over expressed & cell get die. ï¶ But when R1 plasmid is get inherited ,it having the sok gene & sok promotor. ï¶ Then it transcripts sok gene & it is get over expressed against hok gene.
- 6. PURPOSE ANTISENSE SYSTEM ï¶ The Flavr savr tomato is the best example of purpose antisense RNA technology. ï¶ In normal tomato have a PTOM6 gene for tomato ripening process. ï¶ This PTOM6 gene produce polygalacturonase (PG) enzyme . The PG is the major cell wall degrading enzyme of tomato fruit. ï¶ It is developmentally regulated and is synthesized de novo is ripening fruit. ï¶ The FLAVR SAVR tomato was developed through the use of antisense RNA to regulate the expression of the enzyme polygacturonase (PG) in ripening tomato fruit. ï¶ we are purposely introduced a gene in plant which synthesize a complementary mRNA to polygalacturonase (PG) gene and inhibiting the synthesis of polygalacturonase enzyme. ï¶ ripe tomatoes produced in this way will not rot for 3 weeks.
- 8. MECHANISM ï¶ In this technique , short segments of single standard RNA are introduced . ï¶ These oligonucleotides are complementary to the mRNA which physically bind to the mRNA. ï¶ So, they block the expression of particular gene . ï¶ In the of virues , antisense oligonucleotides inhibit viral replication with blocking expression of integrated proviral genes. ï¶ Usually consists of 15-20 nucleotides . ï¶ Translation of mRNA may be blocked by two possible mechanisms , these are : 1. By base specific hybridization : which prevents access by translation machinery i.e. hybridization arrest . 2. By forming RNA/DNA duplex : which is recognized by nuclease Rnase H , specific for digesting RNA in an RNA/DNA duplex. ï¶ RNase H is a non specific endonuclease , catalyzes the cleavage of RNA via hydrolytic mechanism.
- 10. APPLICATIONS ï¶ Flavr savr tomato : Antisense RNA used against an enzyme polygacturonase , an softening enzyme which is responsible for ripening . ï¶ Transgenic ACMV : Resistant cassava plants â used against African cassava mosaic virus (ACMV) which causes cassava mosaic disease causing major economic loss in Africa. ï¶ Formivirsen â is the first antiviral drug developed against CMV.