1. DREB genes play an important role in improving crop tolerance to stresses like drought, salt, and cold. DREB transcription factors regulate stress-responsive genes allowing plants to adapt.
2. Case studies showed overexpression of DREB genes enhanced stress tolerance in crops like rice and sugarcane. Co-transformation with DREB and other stress genes improved tolerance more than single DREB genes.
3. DREB genes respond differently to various stresses. DREB1 genes respond mainly to cold while DREB2 genes respond to dehydration and heat. Proper expression analysis of DREB genes is important for abiotic stress tolerance in transgenic crops.
The document summarizes research on the dechlorination of polychlorinated biphenyl (PCB) congeners by the anaerobic bacterium Dehalococcoides. Key findings include:
1) Dehalococcoides uses PCBs as a terminal electron acceptor and can effectively dechlorinate various PCB mixtures.
2) Experiments showed some PCB congeners (234 CB and 2345 CB) underwent more dechlorination than others (245 CB and 235 CB).
3) Further research is needed to understand congener specificity and identify reductive dehalogenase enzymes responsible for dechlorinating different PCBs.
Application of Reverse Transcriptase-PCR-DGGE as a rapid method for routine d...Laura Maria Lopez Franco
This document discusses using PCR-DGGE and Reverse Transcriptase-PCR DGGE (Rev-T-PCR-DGGE) techniques to detect Vibrio bacteria in food samples. The objective was to evaluate these techniques for detecting Vibrios and to apply them to screen food samples. The methods section describes growing bacterial strains, extracting RNA and DNA, and using PCR and DGGE to analyze samples. The results section shows DGGE gels of Vibrio reference strains and food samples. It was found that Rev-T-PCR-DGGE has a lower detection limit than standard methods and sensitivity increases with pre-enrichment. The conclusions state that Rev-T-PCR
Antisense RNA technology & its role in crop improvement ppt surendra singhDrSurendraSingh2
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.
This lab report details an experiment to construct knockouts of the FAD2 gene in the model plant Thlaspi arvense using RNA interference to reduce unsaturated fatty acid content and improve the quality of seed oil for biodiesel production. The FAD2 gene was amplified from pennycress cDNA using PCR. The amplified FAD2 fragments were inserted into an entry vector, which was then transformed into E. coli cells. Successful transformants were identified through DNA sequencing. The purified FAD2 constructs are now ready to be transformed into a binary vector for plant transformation experiments to knockout the FAD2 gene in pennycress seeds and analyze effects on seed oil composition.
This document summarizes a study on identifying molecular determinants of drought tolerance in coffee plants. It describes analyzing gene expression differences between drought tolerant and susceptible clones of Coffea canephora under controlled drought conditions. Several candidate genes were identified using transcriptomic and proteomic analyses of leaves, including those related to antioxidant activity, photosynthesis, and osmotic adjustment. Higher expression of genes like catalase, mannose-6-phosphate reductase, and PSII proteins were found in drought tolerant clones compared to susceptible clones. The results provide insights into genetic mechanisms of drought tolerance in coffee that can guide breeding programs.
The document describes experiments to develop a large-scale process for producing coenzyme F420 from dewatered sludge waste. Initial lab-scale experiments showed that a mixed bed ion exchange resin could effectively bind and elute F420. Larger scale trials in fermentors and carboys demonstrated that autoclaving, centrifugation, and ion exchange could extract and recover a portion of the available F420, though losses occurred during filtration steps. Further optimization may enhance the extraction efficiency and yield a viable industrial process.
1) Abscisic acid (ABA) induces stomatal closure in pea plants by raising both the cytosolic pH and nitric oxide (NO) levels in guard cells.
2) The rise in cytosolic pH occurs earlier than the increase in NO, suggesting that pH increases are upstream of NO production during ABA-induced stomatal closure.
3) Modulators that raise cytosolic pH like methylamine enhance stomatal closure and NO production by ABA, while agents that lower pH like butyrate prevent the effects of ABA.
1. DREB genes play an important role in improving crop tolerance to stresses like drought, salt, and cold. DREB transcription factors regulate stress-responsive genes allowing plants to adapt.
2. Case studies showed overexpression of DREB genes enhanced stress tolerance in crops like rice and sugarcane. Co-transformation with DREB and other stress genes improved tolerance more than single DREB genes.
3. DREB genes respond differently to various stresses. DREB1 genes respond mainly to cold while DREB2 genes respond to dehydration and heat. Proper expression analysis of DREB genes is important for abiotic stress tolerance in transgenic crops.
The document summarizes research on the dechlorination of polychlorinated biphenyl (PCB) congeners by the anaerobic bacterium Dehalococcoides. Key findings include:
1) Dehalococcoides uses PCBs as a terminal electron acceptor and can effectively dechlorinate various PCB mixtures.
2) Experiments showed some PCB congeners (234 CB and 2345 CB) underwent more dechlorination than others (245 CB and 235 CB).
3) Further research is needed to understand congener specificity and identify reductive dehalogenase enzymes responsible for dechlorinating different PCBs.
Application of Reverse Transcriptase-PCR-DGGE as a rapid method for routine d...Laura Maria Lopez Franco
This document discusses using PCR-DGGE and Reverse Transcriptase-PCR DGGE (Rev-T-PCR-DGGE) techniques to detect Vibrio bacteria in food samples. The objective was to evaluate these techniques for detecting Vibrios and to apply them to screen food samples. The methods section describes growing bacterial strains, extracting RNA and DNA, and using PCR and DGGE to analyze samples. The results section shows DGGE gels of Vibrio reference strains and food samples. It was found that Rev-T-PCR-DGGE has a lower detection limit than standard methods and sensitivity increases with pre-enrichment. The conclusions state that Rev-T-PCR
Antisense RNA technology & its role in crop improvement ppt surendra singhDrSurendraSingh2
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.
This lab report details an experiment to construct knockouts of the FAD2 gene in the model plant Thlaspi arvense using RNA interference to reduce unsaturated fatty acid content and improve the quality of seed oil for biodiesel production. The FAD2 gene was amplified from pennycress cDNA using PCR. The amplified FAD2 fragments were inserted into an entry vector, which was then transformed into E. coli cells. Successful transformants were identified through DNA sequencing. The purified FAD2 constructs are now ready to be transformed into a binary vector for plant transformation experiments to knockout the FAD2 gene in pennycress seeds and analyze effects on seed oil composition.
This document summarizes a study on identifying molecular determinants of drought tolerance in coffee plants. It describes analyzing gene expression differences between drought tolerant and susceptible clones of Coffea canephora under controlled drought conditions. Several candidate genes were identified using transcriptomic and proteomic analyses of leaves, including those related to antioxidant activity, photosynthesis, and osmotic adjustment. Higher expression of genes like catalase, mannose-6-phosphate reductase, and PSII proteins were found in drought tolerant clones compared to susceptible clones. The results provide insights into genetic mechanisms of drought tolerance in coffee that can guide breeding programs.
The document describes experiments to develop a large-scale process for producing coenzyme F420 from dewatered sludge waste. Initial lab-scale experiments showed that a mixed bed ion exchange resin could effectively bind and elute F420. Larger scale trials in fermentors and carboys demonstrated that autoclaving, centrifugation, and ion exchange could extract and recover a portion of the available F420, though losses occurred during filtration steps. Further optimization may enhance the extraction efficiency and yield a viable industrial process.
1) Abscisic acid (ABA) induces stomatal closure in pea plants by raising both the cytosolic pH and nitric oxide (NO) levels in guard cells.
2) The rise in cytosolic pH occurs earlier than the increase in NO, suggesting that pH increases are upstream of NO production during ABA-induced stomatal closure.
3) Modulators that raise cytosolic pH like methylamine enhance stomatal closure and NO production by ABA, while agents that lower pH like butyrate prevent the effects of ABA.
NativeFolderTM is a bacterial culture medium specially formulated to promote the folding and the expression of soluble recombinant proteins in E. coli. NativeFolderTM contains proprietary compounds that prevent protein aggregation and misfolding during protein expression. Don’t waste your time experimenting with the renaturation of inclusion bodies. Use NativeFolderTM and express your correctly folded target protein in the soluble fraction. Simply add water to the provided mix, autoclave and filter sterilize. Recombinant proteins of up to 110 kDa were successfully expressed as soluble fractions using NativeFolderTM.
Inhibition of ζ carotene desaturase gene in chiliVaibhav Maurya
This document outlines a research project aiming to inhibit the expression of the ζ-carotene desaturase gene in capsicum annuum (chili peppers). The objectives are to study the functional role of this gene in chili and its effects on other genes in the carotenoid biosynthesis pathway. The project involves three phases: 1) transforming chili plants to insert an antisense version of the target gene, 2) analyzing gene expression levels using real-time PCR, and 3) profiling metabolites using GC-MS to compare levels in transgenic versus wild-type plants. The goal is to better understand the role of the ζ-carotene desaturase gene and effects of its inhibition on carotenoid biosynthesis in
Pol alpha phosphorylation NAR 00021-0119 (dragged)Hyunsun Park
This study investigated the status of DNA polymerase alpha in fission yeast (Schizosaccharomyces pombe) at different stages of the cell cycle. The researchers found that:
1) DNA polymerase alpha is phosphorylated to a higher level in late S phase cells compared to G2/M phase cells. However, the steady-state level of phosphorylation did not vary during the cell cycle.
2) The phosphorylation sites differed between late S phase and G2/M phase.
3) DNA polymerase alpha partially purified from G1/S phase cells had a different mobility and higher affinity for single-stranded DNA than that from G2/M phase cells.
4) Despite these differences, the in
Namrata singh -recombinant dna technologyNamrata Singh
Recombinant DNA technology ( also known as genetic engineering) is the set of techniques that enable the DNA to be identified, isolated and recombined so that new characteristics can be introduced into the genome of organism. It was largely the work of Paul Berg, Herbert W. Boyer and Stanley N Cohen, although many other scientists made important contributions to the new technology as well.One important aspect of Recombinant DNA Technology is DNA Cloning.
DNA damage repair Neil3 gene Knockout in MOLT-4iosrjce
RNAi is superannuated cellular mechanism that protect organism against viruses that replicate
through double- stranded RNA. RNAi can be used to diminish gene expression from plasmid expressing and
inserted sequence repeat. A stable harpin would be expressed after the vector was integrated into the genome.
In this paper a shiRNA expressing vector for Neil3 was designed and developed which is capable of replication
in MOLT-4. This shiRNA vector had the ability to arose the RNAi pathway, and reduce the gene expression of
Neil3. This was assessed by using pSilence 4.1CMV as a vector, and Gapdh as positive control.
GenTegra RNA Overview - Short & long term stabilizationkbebak
GenTegra RNA is a product that stabilizes RNA samples at ambient temperature for long-term storage, transport, and handling. According to ongoing experiments, RNA samples preserved with GenTegra RNA showed no degradation after 3.5 years of mixed temperature dry state storage at ambient temperature. After rehydration, the samples performed identically to frozen controls in downstream applications. GenTegra RNA protects RNA samples by stopping RNase activity in solution and preventing hydrolysis and oxidation when dried, allowing indefinite storage at ambient temperature.
Agrobacterium Tumefaciens Mediated Transformation Of ArabidopsisThảo Vy Huỳnh Nguyên
1) Arabidopsis thaliana root explants were found to regenerate shoots rapidly and efficiently under the right culture conditions.
2) A transformation procedure was developed using Agrobacterium tumefaciens to introduce a kanamycin resistance gene into Arabidopsis roots, allowing selection of transformed shoots.
3) Using this method, the authors obtained transformed Arabidopsis plants producing seeds within 3 months of gene transfer, demonstrating efficient genetic transformation of this model plant species.
Differential Gene Expression in Lead-exposed Saccharomyces cerevisiaeprekshabhagchandani
This document summarizes a student's research project analyzing differential gene expression in the yeast Saccharomyces cerevisiae exposed to varying concentrations of lead. The student examines 10 genes associated with lead exposure and neurological processes in humans. Results show that heat shock proteins HSP10 and DED81 are upregulated with lead exposure, except at very high concentrations that decrease cell viability. Differential expression in yeast models similar responses in human genomes, helping elucidate molecular mechanisms of neurotoxic effects of lead. Further research with more genes and lower lead concentrations may provide additional insights.
This study aims to analyze conserved amino acids in GAPDH proteins from tropical plants Oxalis corniculata and Plectranthus amboinicus. GAPDH is important for energy production. Previous work cloned GAPDH genes from these plants and Myrtaceae psidium. Psidium showed no cloning and was eliminated. The current work will sequence the cloned GAPDH inserts and analyze conserved amino acids related to catalytic function through bioinformatics. This adds to knowledge of important plant genes and their evolution.
This document summarizes research investigating the biosynthesis and processing of succinate dehydrogenase (SDH) subunits in cultured mammalian cells. The key points are:
1. Antisera were produced against purified bovine heart SDH and its large and small subunits, which detected precursor and mature forms of the subunits in rat, pig, and bovine cell lines.
2. In pig kidney cells, newly synthesized precursors of the large and small SDH subunits were detected that were 1000-2000 and 4000-5000 Da larger than the mature forms, respectively.
3. Pulse-chase experiments showed the precursor forms were fully processed to the mature subunits within 45 minutes when uncouplers of
Microbial biosensors structure and mechanism Reza Khedmati
1) The document discusses the use of biosensors for detecting heavy metals using bioluminescent bacterial sensors. It describes how reporter genes like luciferase are induced by heavy metals, causing the bacteria to luminesce.
2) Methods of immobilizing bacteria in calcium alginate beads for use in biosensors are covered. The document also examines how biosensors can be used to test environmental samples and monitor toxicity over time and with reuse.
3) Detection techniques like colorimetric assays are discussed, where changes in color can indicate heavy metal presence without specialized instruments. The document evaluates biosensor performance in detecting various heavy metals in water and soil.
Recombinant DNA technology involves intentionally modifying organisms' genomes for practical purposes such as eliminating undesirable traits, combining beneficial traits from different organisms, or creating organisms that synthesize useful products. The key steps involve isolating a gene of interest, inserting it into a plasmid, introducing the plasmid into bacteria, and harvesting copies of the gene or its protein products. Common tools used include mutagens, reverse transcriptase to synthesize cDNA, synthetic nucleic acids, restriction enzymes to cut DNA at specific sites, vectors to deliver genes into cells, and gene libraries containing collections of cloned genes.
This document discusses recombinant DNA technology and DNA cloning. It describes several methods for cloning DNA, including plasmid cloning, bacteriophage lambda cloning, and yeast artificial chromosome cloning. The key steps in DNA cloning are fragmentation of DNA, ligation of DNA fragments, transfection into host cells, and screening of cells. Recombinant DNA libraries, such as genomic libraries and cDNA libraries, allow storage and identification of cloned DNA fragments.
This study analyzed differential gene expression in the yeast Saccharomyces cerevisiae when exposed to varying concentrations of lead. The purpose was to use yeast as a model organism to study the molecular mechanisms behind the neurological effects of lead exposure in humans. Specifically, the expression of 10 genes expected to be affected by lead exposure based on human studies was analyzed. The results showed that two genes, HSP10 and DED81, were upregulated as the lead concentration increased, as expected based on their human homologs. However, DED81 expression decreased at the highest lead concentration, possibly due to toxicity effects on cell viability. Further testing is needed to better understand gene expression changes at different lead concentrations.
The document describes the identification, cloning, sequencing, and characterization of the a-L-arabinofuranosidase B (abfB) gene from the phytopathogenic fungus Fusarium oxysporum f. sp. dianthi (Fod). The gene was identified using random amplified polymorphic DNA and encodes a protein of 499 amino acids. The recombinant protein expressed in E. coli had arabinofuranosidase activity and optimal activity at pH 4.0 and 50°C. Reverse transcription PCR showed that the abfB gene is actively transcribed in carnation plants infected with Fod, suggesting it plays a role in the fungus's pathogenicity.
Recombinant DNA technology involves joining DNA molecules from different species and inserting them into a host organism to produce new genetic combinations. This results in recombinant proteins being expressed within living cells. The process involves cloning the gene of interest and inserting it into a plasmid vector. This recombinant DNA is then transferred into a host cell, such as E. coli, and the transformed cells are selected and grown to produce the protein encoded by the inserted gene.
Recombinant DNA technology and its applicationsPragati Randive
Recombinant DNA technology involves combining DNA from different sources. The basic steps include DNA extraction, gene cloning, gene design, transformation, and backcross breeding. Gene cloning involves isolating a single copy of a gene and obtaining indefinite identical copies, which can be done in vivo using restriction enzymes and ligases or in vitro using PCR. Applications of recombinant DNA technology in crop improvement include distant hybridization, developing transgenic plants, developing root nodules in cereal crops, and developing C4 plants. Examples discussed include Golden Rice, Bt Cotton, and Flavr Savr Tomato.
RNAi – Mechanism and Its Application In Crop Improvementkundan Jadhao
This document summarizes an RNAi presentation on crop improvement using RNA interference. The 3-sentence summary is:
RNA interference (RNAi) is a process of post-transcriptional gene silencing mediated by small RNA molecules. The presentation described the RNAi pathway and various applications of RNAi technology in crop improvement, including increasing nutrient levels, developing virus and pest resistance, and reducing anti-nutritional compounds. Several case studies were provided that demonstrated how RNAi has been used to successfully modify traits in different crops like maize, cotton, coffee, and banana.
1) The document discusses the differential localization and functions of PKA regulatory subunits R1b and R2b in the brain.
2) An experiment found that knocking down R1b using shRNA in hippocampal neurons led to decreased levels of pCREB after forskolin treatment, indicating impaired cAMP/PKA/CREB signaling and likely L-LTP impairment.
3) Knocking down R2b did not decrease pCREB levels, suggesting it does not play as important a role in cAMP/PKA/CREB signaling and L-LTP induction.
Cellular signal transduction pathways under abiotic stressSenthil Natesan
Abiotic stresses, especially cold, salinity and drought, are the primary causes of crop loss worldwide. Plant adaptation to environmental stresses is dependent upon the activation of cascades of molecular networks involved in stress perception, signal transduction, and the expression of specific stress-related genes and metabolites. Plants have stress-specific adaptive responses as well as responses which protect the plants from more than one environmental stress. There are multiple stress perception and signaling pathways, some of which are specific, but others may cross-talk at various steps (Knight & knight ,2001).Many cold induced pathways are activated to protect plants from deleterious effects of cold stress, but till date, most studied pathway is ICE-CBF-COR signaling pathway (Miura and Furumoto,2013 ) . The Salt-Overly-Sensitive (SOS) pathway, identified through isolation and study of the sos1, sos2, and sos3 mutants, is essential for maintaining favorable ion ratios in the cytoplasm and for tolerance of salt stress (shi .et al ,2002). Both ABA-dependent and -independent signaling pathways appear to be involved in osmotic stress tolerance (Nakashima and shinozaki, 2013) .ROS play a dual role in the response of plants to abiotic stresses functioning as toxic by-products of stress metabolism, as well as important signal transduction molecules and the ROS signaling networks can control growth, development, and stress response ( Mahajan,s and Tuteja, 2005) .
The document presents a lecture on stress physiology by Adil Zia. It discusses different types of environmental stresses plants face, including drought, flooding, temperature extremes, salinity, and diseases. It explains the mechanisms of injury caused by each stress and the mechanisms of resistance plants have evolved, such as adaptations to reduce water loss or tolerate toxic compounds. The lecture covers topics like membrane damage, metabolic disorders, and accumulation of protective proteins and substances that help plants withstand stressful conditions. It aims to explain how plants resist various stresses through physiological, biochemical and molecular responses.
NativeFolderTM is a bacterial culture medium specially formulated to promote the folding and the expression of soluble recombinant proteins in E. coli. NativeFolderTM contains proprietary compounds that prevent protein aggregation and misfolding during protein expression. Don’t waste your time experimenting with the renaturation of inclusion bodies. Use NativeFolderTM and express your correctly folded target protein in the soluble fraction. Simply add water to the provided mix, autoclave and filter sterilize. Recombinant proteins of up to 110 kDa were successfully expressed as soluble fractions using NativeFolderTM.
Inhibition of ζ carotene desaturase gene in chiliVaibhav Maurya
This document outlines a research project aiming to inhibit the expression of the ζ-carotene desaturase gene in capsicum annuum (chili peppers). The objectives are to study the functional role of this gene in chili and its effects on other genes in the carotenoid biosynthesis pathway. The project involves three phases: 1) transforming chili plants to insert an antisense version of the target gene, 2) analyzing gene expression levels using real-time PCR, and 3) profiling metabolites using GC-MS to compare levels in transgenic versus wild-type plants. The goal is to better understand the role of the ζ-carotene desaturase gene and effects of its inhibition on carotenoid biosynthesis in
Pol alpha phosphorylation NAR 00021-0119 (dragged)Hyunsun Park
This study investigated the status of DNA polymerase alpha in fission yeast (Schizosaccharomyces pombe) at different stages of the cell cycle. The researchers found that:
1) DNA polymerase alpha is phosphorylated to a higher level in late S phase cells compared to G2/M phase cells. However, the steady-state level of phosphorylation did not vary during the cell cycle.
2) The phosphorylation sites differed between late S phase and G2/M phase.
3) DNA polymerase alpha partially purified from G1/S phase cells had a different mobility and higher affinity for single-stranded DNA than that from G2/M phase cells.
4) Despite these differences, the in
Namrata singh -recombinant dna technologyNamrata Singh
Recombinant DNA technology ( also known as genetic engineering) is the set of techniques that enable the DNA to be identified, isolated and recombined so that new characteristics can be introduced into the genome of organism. It was largely the work of Paul Berg, Herbert W. Boyer and Stanley N Cohen, although many other scientists made important contributions to the new technology as well.One important aspect of Recombinant DNA Technology is DNA Cloning.
DNA damage repair Neil3 gene Knockout in MOLT-4iosrjce
RNAi is superannuated cellular mechanism that protect organism against viruses that replicate
through double- stranded RNA. RNAi can be used to diminish gene expression from plasmid expressing and
inserted sequence repeat. A stable harpin would be expressed after the vector was integrated into the genome.
In this paper a shiRNA expressing vector for Neil3 was designed and developed which is capable of replication
in MOLT-4. This shiRNA vector had the ability to arose the RNAi pathway, and reduce the gene expression of
Neil3. This was assessed by using pSilence 4.1CMV as a vector, and Gapdh as positive control.
GenTegra RNA Overview - Short & long term stabilizationkbebak
GenTegra RNA is a product that stabilizes RNA samples at ambient temperature for long-term storage, transport, and handling. According to ongoing experiments, RNA samples preserved with GenTegra RNA showed no degradation after 3.5 years of mixed temperature dry state storage at ambient temperature. After rehydration, the samples performed identically to frozen controls in downstream applications. GenTegra RNA protects RNA samples by stopping RNase activity in solution and preventing hydrolysis and oxidation when dried, allowing indefinite storage at ambient temperature.
Agrobacterium Tumefaciens Mediated Transformation Of ArabidopsisThảo Vy Huỳnh Nguyên
1) Arabidopsis thaliana root explants were found to regenerate shoots rapidly and efficiently under the right culture conditions.
2) A transformation procedure was developed using Agrobacterium tumefaciens to introduce a kanamycin resistance gene into Arabidopsis roots, allowing selection of transformed shoots.
3) Using this method, the authors obtained transformed Arabidopsis plants producing seeds within 3 months of gene transfer, demonstrating efficient genetic transformation of this model plant species.
Differential Gene Expression in Lead-exposed Saccharomyces cerevisiaeprekshabhagchandani
This document summarizes a student's research project analyzing differential gene expression in the yeast Saccharomyces cerevisiae exposed to varying concentrations of lead. The student examines 10 genes associated with lead exposure and neurological processes in humans. Results show that heat shock proteins HSP10 and DED81 are upregulated with lead exposure, except at very high concentrations that decrease cell viability. Differential expression in yeast models similar responses in human genomes, helping elucidate molecular mechanisms of neurotoxic effects of lead. Further research with more genes and lower lead concentrations may provide additional insights.
This study aims to analyze conserved amino acids in GAPDH proteins from tropical plants Oxalis corniculata and Plectranthus amboinicus. GAPDH is important for energy production. Previous work cloned GAPDH genes from these plants and Myrtaceae psidium. Psidium showed no cloning and was eliminated. The current work will sequence the cloned GAPDH inserts and analyze conserved amino acids related to catalytic function through bioinformatics. This adds to knowledge of important plant genes and their evolution.
This document summarizes research investigating the biosynthesis and processing of succinate dehydrogenase (SDH) subunits in cultured mammalian cells. The key points are:
1. Antisera were produced against purified bovine heart SDH and its large and small subunits, which detected precursor and mature forms of the subunits in rat, pig, and bovine cell lines.
2. In pig kidney cells, newly synthesized precursors of the large and small SDH subunits were detected that were 1000-2000 and 4000-5000 Da larger than the mature forms, respectively.
3. Pulse-chase experiments showed the precursor forms were fully processed to the mature subunits within 45 minutes when uncouplers of
Microbial biosensors structure and mechanism Reza Khedmati
1) The document discusses the use of biosensors for detecting heavy metals using bioluminescent bacterial sensors. It describes how reporter genes like luciferase are induced by heavy metals, causing the bacteria to luminesce.
2) Methods of immobilizing bacteria in calcium alginate beads for use in biosensors are covered. The document also examines how biosensors can be used to test environmental samples and monitor toxicity over time and with reuse.
3) Detection techniques like colorimetric assays are discussed, where changes in color can indicate heavy metal presence without specialized instruments. The document evaluates biosensor performance in detecting various heavy metals in water and soil.
Recombinant DNA technology involves intentionally modifying organisms' genomes for practical purposes such as eliminating undesirable traits, combining beneficial traits from different organisms, or creating organisms that synthesize useful products. The key steps involve isolating a gene of interest, inserting it into a plasmid, introducing the plasmid into bacteria, and harvesting copies of the gene or its protein products. Common tools used include mutagens, reverse transcriptase to synthesize cDNA, synthetic nucleic acids, restriction enzymes to cut DNA at specific sites, vectors to deliver genes into cells, and gene libraries containing collections of cloned genes.
This document discusses recombinant DNA technology and DNA cloning. It describes several methods for cloning DNA, including plasmid cloning, bacteriophage lambda cloning, and yeast artificial chromosome cloning. The key steps in DNA cloning are fragmentation of DNA, ligation of DNA fragments, transfection into host cells, and screening of cells. Recombinant DNA libraries, such as genomic libraries and cDNA libraries, allow storage and identification of cloned DNA fragments.
This study analyzed differential gene expression in the yeast Saccharomyces cerevisiae when exposed to varying concentrations of lead. The purpose was to use yeast as a model organism to study the molecular mechanisms behind the neurological effects of lead exposure in humans. Specifically, the expression of 10 genes expected to be affected by lead exposure based on human studies was analyzed. The results showed that two genes, HSP10 and DED81, were upregulated as the lead concentration increased, as expected based on their human homologs. However, DED81 expression decreased at the highest lead concentration, possibly due to toxicity effects on cell viability. Further testing is needed to better understand gene expression changes at different lead concentrations.
The document describes the identification, cloning, sequencing, and characterization of the a-L-arabinofuranosidase B (abfB) gene from the phytopathogenic fungus Fusarium oxysporum f. sp. dianthi (Fod). The gene was identified using random amplified polymorphic DNA and encodes a protein of 499 amino acids. The recombinant protein expressed in E. coli had arabinofuranosidase activity and optimal activity at pH 4.0 and 50°C. Reverse transcription PCR showed that the abfB gene is actively transcribed in carnation plants infected with Fod, suggesting it plays a role in the fungus's pathogenicity.
Recombinant DNA technology involves joining DNA molecules from different species and inserting them into a host organism to produce new genetic combinations. This results in recombinant proteins being expressed within living cells. The process involves cloning the gene of interest and inserting it into a plasmid vector. This recombinant DNA is then transferred into a host cell, such as E. coli, and the transformed cells are selected and grown to produce the protein encoded by the inserted gene.
Recombinant DNA technology and its applicationsPragati Randive
Recombinant DNA technology involves combining DNA from different sources. The basic steps include DNA extraction, gene cloning, gene design, transformation, and backcross breeding. Gene cloning involves isolating a single copy of a gene and obtaining indefinite identical copies, which can be done in vivo using restriction enzymes and ligases or in vitro using PCR. Applications of recombinant DNA technology in crop improvement include distant hybridization, developing transgenic plants, developing root nodules in cereal crops, and developing C4 plants. Examples discussed include Golden Rice, Bt Cotton, and Flavr Savr Tomato.
RNAi – Mechanism and Its Application In Crop Improvementkundan Jadhao
This document summarizes an RNAi presentation on crop improvement using RNA interference. The 3-sentence summary is:
RNA interference (RNAi) is a process of post-transcriptional gene silencing mediated by small RNA molecules. The presentation described the RNAi pathway and various applications of RNAi technology in crop improvement, including increasing nutrient levels, developing virus and pest resistance, and reducing anti-nutritional compounds. Several case studies were provided that demonstrated how RNAi has been used to successfully modify traits in different crops like maize, cotton, coffee, and banana.
1) The document discusses the differential localization and functions of PKA regulatory subunits R1b and R2b in the brain.
2) An experiment found that knocking down R1b using shRNA in hippocampal neurons led to decreased levels of pCREB after forskolin treatment, indicating impaired cAMP/PKA/CREB signaling and likely L-LTP impairment.
3) Knocking down R2b did not decrease pCREB levels, suggesting it does not play as important a role in cAMP/PKA/CREB signaling and L-LTP induction.
Cellular signal transduction pathways under abiotic stressSenthil Natesan
Abiotic stresses, especially cold, salinity and drought, are the primary causes of crop loss worldwide. Plant adaptation to environmental stresses is dependent upon the activation of cascades of molecular networks involved in stress perception, signal transduction, and the expression of specific stress-related genes and metabolites. Plants have stress-specific adaptive responses as well as responses which protect the plants from more than one environmental stress. There are multiple stress perception and signaling pathways, some of which are specific, but others may cross-talk at various steps (Knight & knight ,2001).Many cold induced pathways are activated to protect plants from deleterious effects of cold stress, but till date, most studied pathway is ICE-CBF-COR signaling pathway (Miura and Furumoto,2013 ) . The Salt-Overly-Sensitive (SOS) pathway, identified through isolation and study of the sos1, sos2, and sos3 mutants, is essential for maintaining favorable ion ratios in the cytoplasm and for tolerance of salt stress (shi .et al ,2002). Both ABA-dependent and -independent signaling pathways appear to be involved in osmotic stress tolerance (Nakashima and shinozaki, 2013) .ROS play a dual role in the response of plants to abiotic stresses functioning as toxic by-products of stress metabolism, as well as important signal transduction molecules and the ROS signaling networks can control growth, development, and stress response ( Mahajan,s and Tuteja, 2005) .
The document presents a lecture on stress physiology by Adil Zia. It discusses different types of environmental stresses plants face, including drought, flooding, temperature extremes, salinity, and diseases. It explains the mechanisms of injury caused by each stress and the mechanisms of resistance plants have evolved, such as adaptations to reduce water loss or tolerate toxic compounds. The lecture covers topics like membrane damage, metabolic disorders, and accumulation of protective proteins and substances that help plants withstand stressful conditions. It aims to explain how plants resist various stresses through physiological, biochemical and molecular responses.
The document discusses the stay-green trait in crops. It begins with an introduction to stay-green, which is a heritable trait that delays foliar senescence. This allows plants to maintain photosynthetic activity even under post-anthesis drought stress, leading to higher yields. The document then covers the history, significance, types, relationship to chlorophyll and nitrogen remobilization, role of hormones and transcription factors, breeding considerations, and presence in different crops. Stay-green is significant for traits like drought resistance and enhanced nitrogen recycling. Genes involved include SGR chlorophyll degradation genes and various transcription factors that regulate senescence. Breeding efforts aim to select high-yielding stay-green varieties suited for
Transcriptional profiling of Halobacterium sp. NRC-1 showed changes in gene expression in response to changes in salinity and temperature. Growth under high salt stress resulted in modulation of genes for ion transporters like potassium and phosphate transporters. Growth at cold temperatures altered expression of genes for lipid metabolism, gas vesicles, and cold shock proteins. Heat shock induced several chaperone genes. The study provides insights into Halobacterium's responses to environmental stresses at the gene expression level.
Physiological and molecular basis of drought tolerance in riceAlex Harley
This document summarizes a seminar on the physiological and molecular mechanisms of drought tolerance in rice. It discusses mechanisms such as osmoregulation through proline accumulation, antioxidant systems like ascorbate-glutathione pathways, and signaling molecules like ABA. It also describes quantitative trait loci (QTLs) linked to drought tolerance that have been identified, including qDTY12.1. Finally, it discusses transgenic approaches to improving drought tolerance by overexpressing genes involved in traits like root growth, osmoprotectant synthesis, and transcription factor regulation.
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This thesis analyzes alterations in hypersensitive response and senescence rate in BLADE-ON-PETIOLE 1/2 (BOP1/2) mutant Arabidopsis plants. BOP1/2 are involved in plant defense responses. The thesis finds that BOP1/2 mutants exhibit runaway cell death during hypersensitive response to pathogens. It also finds that BOP1/2 mutants have delayed senescence and organ production under short day conditions. This suggests BOP1/2 may regulate senescence rate by modulating plant defense pathways.
Abscisic acid (ABA) is a plant hormone involved in various developmental processes. It promotes stomatal closing, induces bud and seed dormancy, and provides drought tolerance. ABA is synthesized from carotenoids in chloroplasts and transported throughout the plant. Its signal transduction pathway involves membrane and cytosolic receptors that regulate ion channels and transcription factors. ABA plays key roles in adaptation to environmental stresses.
The document summarizes research on the nitrogen-fixing bacterium Rhizobium etli and its two rpoN genes, rpoN1 and rpoN2. The key findings are:
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2) RpoN1 and rpoN2 are differentially expressed, with rpoN1 expressed during free-living conditions and rpoN2 expressed during symbiosis.
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Desalination and Water Recycling through Aquaporin - A composite power point ...Karthik Raman
We propose in brief in this powerpoint about the technology driver of the future of desalination.
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Our research & development team incorporates the top scientists of the world with hundreds and thousands of man-hours put into studying this and related fields and we are in the verge of taking our insignts to the next level of commercialization.
This document identifies and analyzes aquaporin genes in barley in response to salt stress. It isolates several new aquaporin genes (HvPIPs) in barley. It finds that under salt stress, transcription of several HvPIP genes decreases more in salt-sensitive barley compared to salt-tolerant barley. HvPIP2;3 and HvPIP2;4 showed high water transport activity, while HvPIP1;2 did not, but coexpression of HvPIP1;2 with HvPIP2;1 or HvPIP2;4 increased water permeability. Downregulation of some PIP genes under salt stress may limit water loss.
A conserved Ser/Arg rich motif in PPZ orthologs from fungi is important for i...AnnuMinhas
Background - Ppz1 orthologs - novel family of
phosphatases - have unique N-terminal non
catalytic domain
Results – Ppz1 ortholog from halotolerant yeast
Debaryomyces hansenii plays important role in
salt tolerance, cell wall integrity and cell growth
in through distinct mechanism.
Conclusion – Short serine arginine rich motif in
non-catalytic domain is essential for its role in
salt tolerance.
Significance – This motif is conserved among
orthologs and functionally important.
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Similar to Overexpression of PI2:5 Aquaporin In Arabidopsis (20)
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Odoo 17 CRM allows us to track why we lose sales opportunities with "Lost Reasons." This helps analyze our sales process and identify areas for improvement. Here's how to configure lost reasons in Odoo 17 CRM
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1. Overexpression of PIP2;5 Aquaporin
Alleviates Effects
of Low Root Temperature on Cell
Hydraulic Conductivity
and Growth in Arabidopsis
Proponents:
Seong Hee Lee Gap Chae Chung
Ji Young Jang Sung Ju Ahn
Janusz J. Zwiazek Julius Manolong
Ric Solijon
2.
3. • Low soil temperature restricts the growth and
yield of plants.
• Growth reduction is accompanied by
reduction of water uptake.
• not surprising that low temperature tolerance
has been often correlated with drought
resistance.
4. • Reduced water flux at low temperatures is
thought to occur due to higher water viscosity
and the inhibition of transmembrane water
transport.
• The ability of plants to maintain the
transmembrane waterflow may be among the
key factors linked to chilling tolerance.
6. • Transmembrane water flow is regulated by
aquaporins.
4 subfamilies:
1. Plasma membrane intrinsic proteins (PIPs)
2. Tonoplast intrinsic proteins (TIPs)
3. Nodulin-like intrinsic proteins (NIPs)
4. Intrinsic proteins
7. • Problems:
1. the effects of low temperature on aquaporin
expression are not always clear, with down-
regulation of some aquaporins.
2. less is known about the effects of low
temperature on aquaporin gating, which
regulates water flux through protein
conformational changes
9. • Use of Arabidopsis with overexpressed PIP1;4
and PIP2;5
• Subjected Arabidopsis roots to low
temperature (10°C) whereas the shoots of
plants were exposed to high transpirational
demand conditions (23°C/21°C day/night
temperatures).
• Used several inhibitors of protein
phosphorylation and dephosphorylation
10. HYPOTHESES
(1) the impact of low temperature on root
water transport involves aquaporin gating
through the phosphorylation/
dephosphorylation processes, and
(2) Overexpression of the low-temperature-
responsive aquaporins PIP1;4 and PIP2;5 would
help the plants maintain high Lp values and, in
consequence, high growth rates when their
roots are exposed to low temperature.
11.
12. Effects of Low Root Temperature on Relative Growth Rates:
Figure 1. Shoot (A)
and root (B) relative
growth
rates in wild-type
Arabidopsis plants and
in plants
overexpressing PIP1;4
and PIP2;5.
15. Effects of Low Temperature on T1/2 and Lp
Figure 3. Typical
results of
descending
and ascending
temperature effects
on
T1/2 in individual
cortical cells of
Arabidopsis
roots.
16. Effects of Ca(NO3)2, LaCl3, and Protein Phosphatase
Inhibitors on Lp
• 1. 1 mM LaCl3 (calcium channel blocker) in the
wild-type plants at 25°C resulted in an over 2-fold
decrease in Lp
• The addition of 5 mM Ca(NO3)2at 25°C showed
no effect on Lp
• 5 mM Ca(NO3)2 was added at 10°C, the value of
Lp was increased almost to the same level as the
one measured at 25°C
17. • 1 mM Na3VO4 and 75 mM okadaic acid
increased Lp when added to roots at 10°C
Figure 4. Effect of temperature
and exogenous treatments on
Lp. A, Effects of descending root
temperatures (25°C, 20°C, 15°C,
and 10°C) followed by the
ascending root temperature of
25°C on Lp. B, Lp values in roots
of plants subjected to 10°C for 1
and 5 d and in roots exposed to
25°C.
18. Activation Energy for Root Water Transport
Activation energy (Ea) for Lp was 63 kJ mol21 in the
wild-type plants (Table III). In both PIP overexpression
plants, Ea values for Lp were below 10 kJ mol-1
19. Relative Expression Profiles of the 13 PIP Genes in
Arabidopsis Exposed to Low-Temperature Stresses
Figure 5. Analyses of
PIP expression. A,
Relative expression
profile of the 13 PIP
genes in roots of 3-
week-old wild-type
Arabidopsis seedlings
at a root temperature
of 23°C.
20. • the reduction of Lp in the wild-type plants at
10°C was reversed to as much as 70% of the
preexposure level by the addition of 5 mM
Ca(NO3)2 and protein phosphatase inhibitors
(75 nM okadaic acid and 1 mM Na3VO4),
• Okadaic acid and vanadate are commonly
used as inhibitors of protein phosphorylation
(Cohen and Cohen, 1989; Gordon, 1991).
21. • calcium channel blocker,1 mM LaCl3,
significantly inhibited Lp at 25°C, further
supporting the notion that aquaporin gating is
linkedto the calcium signal
• Some PIPS and tonoplast intrinsic preoteins
are insensitive to mercury but many are
blocked.
22. • Overexpression of aquaporins in plants
alleviates the effect of mercury on Lp, likely
because the inhibition of water transport by
mercury is only partial and there are more
water-transporting channels present in the
PIP-overexpressing plants.
• PIP1;4 and PIP2;5 do not have Cys-189, which
is known to be present in many mercury-
sensitive aquaporins.
23. • In higher concentrations, mercury can also
inhibit water transport by acting as a
nonspecific metabolic inhibitor (Wan and
Zwiazek, 1999; Zhang and Tyerman, 1999).
• the inhibition of Lp was less effective in
Arabidopsis plants overexpressing PIP1;4 and
PIP2;5 compared with the wild-type plants,
reflecting the increased aquaporin abundance
and the watertransporting functionality of
both PIPs.
24. • wild-type plants demonstrate a high
dependency of cell water transport on
temperature in Arabidopsis roots.
• the 7- to 9-fold lower Ea values measured in
PIP1;4 and PIP2;5 overexpression lines provide
strong evidence for the importance of these
proteins in cell water transport at low
temperature.
25. Table 4. Activation energy differencess
Ea (kJ mol-1)
Water across membrane thru less than 25
channels
Water across the lipid bilayer 46–63
Higher plants 18 to 48
Tradescantia virginiana 186
Cucumber root cortical cells 100
Nicotiana tabacum 57
26.
27. • Overexpression of PIP1;4 and PIP2;5 in
Arabidopsis was effective in alleviating the
short-term effects of low root temperature on
Lp in root cells.
• But alleviation was no longer present after 5 d
of root exposure to 10°C in plants
overexpressing PIP1;4
28. • The temperature sensitivity of cell water
transport in Arabidopsis roots :
-the reductions in shoot and root growth
rates in the wild-type and PIP1;4-overexpressing
plants exposed to 10°C root temperature for 5
days.
• But no effects on PIP2;5
29. • The inhibition of Lp by low temperature could
be partially prevented by the application of
Ca(NO3)2 and by protein phosphatase
inhibitors
• low temperature sensitivity of root water
transport may be connected to the aquaporin
phosphorylation/dephosphorylation
processes.
30. “The best thing you can do is the right thing; the next best thing you
can do is the wrong thing; the worst thing you can do is nothing.” -
Theodore Roosevelt