Mitochondria are organelles found in plant cells that provide energy and regulate important metabolic processes. Plant mitochondrial genomes vary significantly in size but generally encode proteins involved in oxidative phosphorylation as well as rRNAs and tRNAs. These genomes often contain introns, open reading frames, and chloroplast DNA sequences. Mutations in mitochondrial DNA can impact plant development and cause cytoplasmic male sterility. Expression of chimeric mitochondrial genes is associated with some cases of male sterility. Studies examine the role of mitochondrial proteins like uncoupling proteins and alternative oxidases in conferring stress tolerance in plants. The WA352 mitochondrial gene is implicated in cytoplasmic male sterility in rice through interaction with the nuclear-encoded protein COX11.
genetic engineering, principles, b pharma 6th sem, biotechnology
What is a gene ?
Definition
History
Process
Molecular tools of genetic engineering
Restriction enzymes
History of restriction enzyme
Mechanism of action
Types of restriction enzymes
Application of restriction enzymes
Blunt ends
Sticky ends
transgenic
cisgenic.
knockout organism.
Host organism vector
TRANSGENIC PLANTS
DOLLY THE SHIP
TRANSGENIC ANIMALS
pOnebyOne™ are efficient, accurate and flexible Bicistronic Mammalian Expression Kits that contains an Expression Cassette based in 2A sequence breakthrough technology.
Its novel (patent pending) technology allows simultaneous Expression of two Proteins from the same mRNA. Cells transfected with Bicistronic vectors ensure that if one of the Proteins is present, the other one is also present.
Bicistronic Expression vectors are supported on viral elements: the IRES or 2A sequence. IRES has been widely used. It is a relative short sequence, around 600-700 bp, although this length could be a disadvantage in viral vectors where packaging capacity is limited. IRES based Expression vectors are characterized by a non-stoichiometric production of both proteins; generally there is a lower expression of the downstream gene.
Many 2A sequences from several families of viruses have been described for producing multiple polypeptides. 2A mediated cleavage is a universal phenomenon in all eukaryotic cells. With just 20 bp in length, the 2A sequence has been used succesfully to generate multiple proteins in some biological models: plants, zebrafish, transgenic mice or eukaryotic cell lines. Vectors based on 2A produce stoichiometric proportion of both proteins.
Canvax™ offers a ready-to-clone solution of your Gene of Interest, obtained by PCR, onto a wide collection of Bicistronic vectors based on 2A sequence. You can choose among different Promoters, selection Antibiotics or Reporter Genes.
this is a presentation on gene expression vector that includes what is expression vector, how many types of expression vector and difference between cloning and expression vector
genetic engineering, principles, b pharma 6th sem, biotechnology
What is a gene ?
Definition
History
Process
Molecular tools of genetic engineering
Restriction enzymes
History of restriction enzyme
Mechanism of action
Types of restriction enzymes
Application of restriction enzymes
Blunt ends
Sticky ends
transgenic
cisgenic.
knockout organism.
Host organism vector
TRANSGENIC PLANTS
DOLLY THE SHIP
TRANSGENIC ANIMALS
pOnebyOne™ are efficient, accurate and flexible Bicistronic Mammalian Expression Kits that contains an Expression Cassette based in 2A sequence breakthrough technology.
Its novel (patent pending) technology allows simultaneous Expression of two Proteins from the same mRNA. Cells transfected with Bicistronic vectors ensure that if one of the Proteins is present, the other one is also present.
Bicistronic Expression vectors are supported on viral elements: the IRES or 2A sequence. IRES has been widely used. It is a relative short sequence, around 600-700 bp, although this length could be a disadvantage in viral vectors where packaging capacity is limited. IRES based Expression vectors are characterized by a non-stoichiometric production of both proteins; generally there is a lower expression of the downstream gene.
Many 2A sequences from several families of viruses have been described for producing multiple polypeptides. 2A mediated cleavage is a universal phenomenon in all eukaryotic cells. With just 20 bp in length, the 2A sequence has been used succesfully to generate multiple proteins in some biological models: plants, zebrafish, transgenic mice or eukaryotic cell lines. Vectors based on 2A produce stoichiometric proportion of both proteins.
Canvax™ offers a ready-to-clone solution of your Gene of Interest, obtained by PCR, onto a wide collection of Bicistronic vectors based on 2A sequence. You can choose among different Promoters, selection Antibiotics or Reporter Genes.
this is a presentation on gene expression vector that includes what is expression vector, how many types of expression vector and difference between cloning and expression vector
This PPT has described how to produce soluble anf high amount of recombinant protein in E.coli host. This PPT has mentioned different expression vectors, different E.coli Expression host strain and other strategies for getting high expression of desired gene.
The content is about the general description of genetic material and further two techniques of biotechnology. The content includes two topics.
Firstly with introduction to biotechnology it describe about DNA, recombinant DNA (rDNA) technology, history, goals, procedure of rDNA technology, tools, techniques, application, demerits and products of rDNA technology.
Second portion entitiled as Hybridoma technology. this includes the basic principle, production of monoclonal antibodies, merits demerits and drugs from monoclonal antibody.
New pharmaceuticals derived from biotechnology is covered in last. All the content is referred from books and internet sources.
This ppts is based upon the recent adavancement and methodology about mitochondrial transformation. What is organellar transformation and what is the importance in contemporary time.
Transcription factors of the nuclear factor κ B family are the paradigm for signaling dependent nuclear translocation and are ideally suited to analysis through image-based chemical genetic screening. The authors describe combining high-content image analysis with a compound screen to identify compounds affecting either nuclear import or export. Validation in silico and in vitro determined an EC50 for the nuclear export blocker leptomycin B of 2.4 ng/mL (4.4 nM). The method demonstrated high selectivity (Z′ >0.95), speed, and robustness in a screen of a compound collection. It identified the IκB protein kinase inhibitor BAY 11 7082 as an import inhibitor, the p38 mitogen-activated protein (MAP) kinase inhibitor PD98509 as an import enhancer, and phorbol ester as an export inhibitor. The results establish a robust method for identifying compounds regulating nucleocy- toplasmic import or export and also implicate MAP kinases in nuclear import of nuclear factor κ B
Expression and purification of recombinant proteins in Bacterial and yeast sy...Shreya Feliz
This presentation gives the information about bacterial and yeast system as host for expressing recombinant proteins, suitable vectors, strains of host, Pros and cons of this system, different purification techniques and commercially available proteins produced so far by this system.
Corynex is a novel Protein Expression system that overcomes some of the most frustrating challenges with common microbial expression systems by secreting fully folded and active proteins directly into the cell medium with minimal host proteins and impurities. This greatly simplifies the entire purification process, lowers costs, and ultimately speeds time to market.
Majority of agronomic traits are quantitative and are controlled polygenetically.Instead of producing transgenic plants through single gene transfer many researchers are attempting on multigene engineering. The simultaneous transfer of multiple genes in to plants will enable us to produce plants with more desirable characters. Engineering of genes coding for complete metabolic pathways, bacterial operons or biopharmaceuticals that require an assembly of complex multisubunit proteins etc are some of the successful examples of multigene engineering.
This PPT has described how to produce soluble anf high amount of recombinant protein in E.coli host. This PPT has mentioned different expression vectors, different E.coli Expression host strain and other strategies for getting high expression of desired gene.
The content is about the general description of genetic material and further two techniques of biotechnology. The content includes two topics.
Firstly with introduction to biotechnology it describe about DNA, recombinant DNA (rDNA) technology, history, goals, procedure of rDNA technology, tools, techniques, application, demerits and products of rDNA technology.
Second portion entitiled as Hybridoma technology. this includes the basic principle, production of monoclonal antibodies, merits demerits and drugs from monoclonal antibody.
New pharmaceuticals derived from biotechnology is covered in last. All the content is referred from books and internet sources.
This ppts is based upon the recent adavancement and methodology about mitochondrial transformation. What is organellar transformation and what is the importance in contemporary time.
Transcription factors of the nuclear factor κ B family are the paradigm for signaling dependent nuclear translocation and are ideally suited to analysis through image-based chemical genetic screening. The authors describe combining high-content image analysis with a compound screen to identify compounds affecting either nuclear import or export. Validation in silico and in vitro determined an EC50 for the nuclear export blocker leptomycin B of 2.4 ng/mL (4.4 nM). The method demonstrated high selectivity (Z′ >0.95), speed, and robustness in a screen of a compound collection. It identified the IκB protein kinase inhibitor BAY 11 7082 as an import inhibitor, the p38 mitogen-activated protein (MAP) kinase inhibitor PD98509 as an import enhancer, and phorbol ester as an export inhibitor. The results establish a robust method for identifying compounds regulating nucleocy- toplasmic import or export and also implicate MAP kinases in nuclear import of nuclear factor κ B
Expression and purification of recombinant proteins in Bacterial and yeast sy...Shreya Feliz
This presentation gives the information about bacterial and yeast system as host for expressing recombinant proteins, suitable vectors, strains of host, Pros and cons of this system, different purification techniques and commercially available proteins produced so far by this system.
Corynex is a novel Protein Expression system that overcomes some of the most frustrating challenges with common microbial expression systems by secreting fully folded and active proteins directly into the cell medium with minimal host proteins and impurities. This greatly simplifies the entire purification process, lowers costs, and ultimately speeds time to market.
Majority of agronomic traits are quantitative and are controlled polygenetically.Instead of producing transgenic plants through single gene transfer many researchers are attempting on multigene engineering. The simultaneous transfer of multiple genes in to plants will enable us to produce plants with more desirable characters. Engineering of genes coding for complete metabolic pathways, bacterial operons or biopharmaceuticals that require an assembly of complex multisubunit proteins etc are some of the successful examples of multigene engineering.
Richard Altman, occurrence of mitochondria and called them bioblast.
Greek word mitos stands for thread and chondros means granule (Carl Benda )
Mitochondria can be created only by the division of the pre-existing mitochondria
Mitochondria are membrane-bound eukaryotic organelles that produce ATP (adenosine triphosphate) in the process of oxidative phosphorylation and tricarboxylic acid cycle.
Involved in regulation of programmed cell death and response to increased oxidative stress produced as a result of high salt, cold and drought conditions
Mitochondrion of land plants is not only almost 100 times larger than the animal mitochondrion
Circular (linear in some fungi and protozoa)
Double stranded
Supercoiled
No histones
Multiple copies located in nucleoids
Contain DNA which codes for mitochondrial proteins, ribosomes, etc.
Divide by a process similar to binary fission when cell divides
In plants the mitochondrial genes may become separated onto different circular molecules by a process of intramolecular recombination
This recombination is mediated by repetitive sequences located in the mtDNA.
An exchange between two of the repetitive sequences can partition the master DNA circle into two smaller circles
Presented by- MD JAKIR HOSSAIN
Doctoral Research Scholar
Department of Agricultural Genetic Engineering ,
Faculty of Agricultural Sciences and Technologies,
Nigde Omer Halisdemir University, Turkey
E. Mail- mjakirbotru@gmail.com
M Pharm Pharmacognosy Semester 2, MEDICINAL PLANT BIOTECHNOLOGY UNIT 1, Introduction to Plant biotechnology: Historical perspectives, prospects for development of plant biotechnology as a source of
medicinal agents. Applications in pharmacy and allied fields. Genetic and molecular biology as applied to pharmacognosy, study of DNA, RNA and protein replication, genetic code, regulation of gene expression, structure and complicity of
genome, cell signaling, DNA recombinant technology.
Extranuclear inheritance or cytoplasmic inheritance is the transmission of genes that occur outside the nucleus. It is found in most eukaryotes and is commonly known to occur in cytoplasmic organelles such as mitochondria and chloroplasts or from cellular parasites like viruses or bacteria. Determining the contribution of organelle genes to plant phenotype is hampered by several factors, including the paucity of variation in the plastid and mitochondrial genomes. Mitochondria are organelles which function to transform energy as a result of cellular respiration. Chloroplasts are organelles which function to produce sugars via photosynthesis in plants and algae. The genes located in mitochondria and chloroplasts are very important for proper cellular function, yet the genomes replicate independently of the DNA located in the nucleus, which is typically arranged in chromosomes that only replicate one time preceding cellular division. The extranuclear genomes of mitochondria and chloroplasts however replicate independently of cell division. They replicate in response to a cell's increasing energy needs which adjust during that cell's lifespan. There is consistent difference between the results from reciprocal crosses; generally only the trait from female parent is transmitted. In most cases, there is no segregation in the F2 and subsequent generations.
Plant genetic engineering is one of the key technologies for crop improvement as well as an emerging approach for producing recombinant proteins in plants. Both plant nuclear and plastid genomes can be genetically modified, yet fundamental functional differences between the eukaryotic genome of the plant cell nucleus and the prokaryotic-like genome of the plastid will have an impact on key characteristics of the resulting transgenic organism. So, which genome, nuclear or plastid, to transform for the desired transgenic phenotype? In this paper we compare the advantages and drawbacks of engineering plant nuclear and plastid genomes to generate transgenic plants with the traits of interest, and evaluate the pros and cons of their use for different biotechnology and basic research applications. The chloroplast is a pivotal organelle in plant cells and eukaryotic algae to carry out photosynthesis, which provides the primary source of the world’s food. The expression of foreign genes in chloroplasts offers several advantages over their expression in the nucleus: high-level expression, no position effects, no vector sequences allowing stable transgene expression. In addition, transgenic chloroplasts are generally not transmitted through pollen grains because of the cytoplasmic localization. In the past two decades, great progress in chloroplast engineering has been made.
Organization and Regulation of Mitochondrial Protein SynthesisHeena36363
PRESENTATION OUTLINE
Basics about mitochondria-size structure and functions
Origin of Mitochondria
Mitochondrial Genetic System
Structure of mt-DNA
Translational requirements of mitochondria
Mitoribosomes
Adaptation Of translation machinery To operate within mitochondria
Translation cycle in mitochondria
Regulation Of mitochondrial translation
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...Ana Luísa Pinho
Functional Magnetic Resonance Imaging (fMRI) provides means to characterize brain activations in response to behavior. However, cognitive neuroscience has been limited to group-level effects referring to the performance of specific tasks. To obtain the functional profile of elementary cognitive mechanisms, the combination of brain responses to many tasks is required. Yet, to date, both structural atlases and parcellation-based activations do not fully account for cognitive function and still present several limitations. Further, they do not adapt overall to individual characteristics. In this talk, I will give an account of deep-behavioral phenotyping strategies, namely data-driven methods in large task-fMRI datasets, to optimize functional brain-data collection and improve inference of effects-of-interest related to mental processes. Key to this approach is the employment of fast multi-functional paradigms rich on features that can be well parametrized and, consequently, facilitate the creation of psycho-physiological constructs to be modelled with imaging data. Particular emphasis will be given to music stimuli when studying high-order cognitive mechanisms, due to their ecological nature and quality to enable complex behavior compounded by discrete entities. I will also discuss how deep-behavioral phenotyping and individualized models applied to neuroimaging data can better account for the subject-specific organization of domain-general cognitive systems in the human brain. Finally, the accumulation of functional brain signatures brings the possibility to clarify relationships among tasks and create a univocal link between brain systems and mental functions through: (1) the development of ontologies proposing an organization of cognitive processes; and (2) brain-network taxonomies describing functional specialization. To this end, tools to improve commensurability in cognitive science are necessary, such as public repositories, ontology-based platforms and automated meta-analysis tools. I will thus discuss some brain-atlasing resources currently under development, and their applicability in cognitive as well as clinical neuroscience.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
4. • Regulate metabolic activity
• Maintains concentration of Calcium ions
• Detoxify ammonia
• Apoptosis
• Aging
Function of Mitochondria
5. Plant mitochondrial genome
Size = ~200kb - 2400kb
Extra genes:
Open Reading Frames
Ribosomal proteins
Universal genetic code.
Arranged as different size circles, sometimes with plasmids
The plant mtDNA contains chloroplast sequences, indicating
exchange of genetic information between organelles
Coding regions are larger than animals and fungi
Smallest mtDNAs -Plasmodium and its relatives (6 kb)
Encode proteins for oxidative phosphorylation
7. Size of mitochondrial genome
Name Scientific Name Size
Liver wort Marchantia polymorpha 186 kb
Maize Zea mays 700 kb
Watermelon Citrullus lanatus 300 kb
Rice Oryza sativa 492 kb
Arabidopsis Arabidopsis thaliana ~367 kb
Squash Cucurbita pepo 1 Mb
Caulobacter Caulobacter crescentus 4.017 Mb
Rhizobium
Bradyrhizobium
japonicum
9.1 Mb
Human Homo sapiens
16.5 kb
White musterd B. hirta 208kb
Muskmelon C melo 2500kb
8. Comparison of mitochondrial genomes
Size
Non-coding DNA
Mutation rate High
Very Low
14kb - 42kb
Recombination
Introns
Universal genetic code
Low
Variable
17kb - 180kb
/
Mostly
Very Low
Very High
184kb - 2,400kb
Animals Fungi Plants
9. Nuclear vs. Mitochondrial DNA
• Nuclear DNA
– found in nucleus of the
cell
– 2 sets of 23 chromosomes
– maternal and paternal
– double helix
– bounded by a nuclear
envelope
– DNA packed into
chromatin
• Mitochondrial DNA
– found in mitochondria of the
cell
– each mitochondria may have
several copies of the single
mt DNA molecule
– maternal only
– circular
– free of a nuclear envelope
– DNA is not packed into
chromatin 9
11. RNA EDITING
Trypanosome mitochondrial cox2 transcripts.
Genomically encoded C residues are converted post-transcriptionally
to U residues.
RNA editing can create new
initiation codons (ACG to
AUG) and new termination
codons (CGA to UGA).
Ex: nad1 initiation codon
created by editing of ACG to
AUG in all known angiosperm
mitochondrial genomes.
12. • common genes for both plant and animal mtDNA for
component of oxidative phosphorilation
• 9 subunit – respiratory – chine complex –I
• 1 sub unit of complex –III(cob)
• 3 sub unit of complex – IV(cox1, cox2, cox3)
• 2 sub unit of complex –V(atp6, atp8)
• rRNA genes
• tRAN genes
• Ribosomal proteins
• Cytochrome c biogenesis (ccm)
• Mtt - B- like transporter
• Apocytochrome b (cob)
• Cytochrome oxidase subunit (cox 1)
• large (26S) and Small(18S) ribosomal RNAs
Gene content of mt genome
20. G C CONTENT
• The base composition of mtDNA is nearly constant among all
sequenced plant mitochondrial genomes
• variable intergenic regions do not exhibit lower or higher average
GC content than does the rest of the genome
• No discrete regions of higher or lower GC content are present in
the genomes.
Z mays NB 43.9%
O sativa 43.9%
B vulgaris 43.9%
A thaliana 44.8%
B napus 45.2%
M polymorpha 42.4%
21. Protein-coding genes, tRNA genes, rRNA genes
Rapeseed 222kb have
54 genes functional
genes
34genes for protein
coding
3 rRNA genes
17 tRNA genes
22. Z mays NB 121
O sativa 113
B vulgaris 93
A thaliana 85
B napus 45
liverwort 32
Open reading frames (ORFS) : reading frame of at least 100 codons with in
frame start and stop codons
Chimeric genes :
•The first chimeric gene-urf13 in the CMS-T mitochondrial genome of maize urf13 is the
cause of the sterility
•The production of proteins resulting from chimeric genes is directly associated with
CMS (maternally inherited trait)
Pseudo genes : defective versions of genes that no longer produce a functional product
23. • Introns : Saccharomyces cerevisiae.
• Classes
• Group I : released as a linear
molecule with a covalently added G
residues
• Group II : released as lariat
structures
• liverwort mitochondrial genome
contains both group I and group II
introns.
• cox1 intron is the only reported
group I intron in the mitochondrial
genomes of vascular plants
Introns
26. Mutations in mitochondria
Mutation rate in mtDNA is very high (10 times)
Large amounts of “reactive oxygen species” (peroxide and
superoxide) are present, and they are quite mutagenic.
The D loop has an especially high rate of mutation
Part of the effects of aging have been attributed to the gradual
loss of mitochondria due to accumulated mutations in individual
cells
27. Mutations in mitochondria
A combination of aberrant, rare and normal, high-frequency
recombination within mitochondrial genomes and between
mitochondrial sub genomes leads to the
origin of deletion mutations such as those responsible for
the non-chromosomal-stripe (NCS) abnormal growth mutants
reversions of cytoplasmic-male-sterile (CMS) plants to
fertility
28. Cytoplasmic male sterility
cytoplasmic male sterility (CMS) in plants is often caused by
the expression of chimeric genes.
Rearrangement mutations can lead to the loss of CMS-
associated sequences from the mtDNA and recovery of male
fertility, a process known as cytoplasmic reversion
NCS mutants
Maternally inherited, abnormal growth mutations (such as
maize NCS) usually reflect deletions within functional
mitochondrial genes coding for subunits of respiratory
complexes or ribosomal proteins.
These mutations affect the plant throughout its life cycle and
are lethal during some stages, particularly seed development.
29. An Arabidopsis Mitochondrial Uncoupling
Protein Confers Tolerance to Drought and
Salt Stress in Transgenic Tobacco Plants.
Kevin Begcy et al.,
August 30, 2011
Orian S. Shirihai, Boston University,
United States of America
Plant Materials: Nicotiana tabacum SR1 plants were transformed with an expression
cassette comprising a double 35S promoter that controls the AtUCP1 gene from A.
thaliana, as described previously. Three independent and homozygous lines of AtUCP1-
expressing tobacco plants (AtUCP1-7, AtUCP1-32, and AtUCP1-49) were chosen for this
study.
30. 30
Figure 1. Seed germination under drought and salt stress. (A) control; equeal 5-80 60
(B)200mM mannitol;10 complet ger 15 did not (C) 300mM mannitol; sign effect
more wt (D) 400 mM mannitol;40% (E) 100 mM Nacl ; 80-95 45%-10d (F) 175 mM
Nacl 50-7d 11d 60
35. Conclusion
The mitochondria of plants share functions
with mitochondria of other eukaryotes, and thus
share many of the same genes. However, the
organization, structure, expression and
evolutionary dynamics of plant mitochondrial
genomes are unusual when compared with those
other organisms. Structurally, plant mitochondrial
genomes are very diverse relative to their fungal
and animal counterparts, both of which tend to be
quite uniform in organization and gene content.
39. Repeated sequences in plant
mitochondrial genomes
• Large repeats are more frequent in larger mitochondrial
genomes and vice versa
• More than 50% of the 369-kb rice 16 repeats at least 1 kb long.
• The 570 kb maize NB mitochondrial genome contains only 8
repeats 1kb or longer, which represent only 17% of the
genome.
40. Nuclear genes control the mitochondria
biogenesis
Transcription
Pre-mRNA processing
Translation of the mRNAs
into mitochondrial proteins
The assembly of
ribosomes and respiratory
complexes and are also
required for the targeting
and degradation of
organellar subunits.
41. Nuclear genes control the mitochondria
biogenesis
Transcription
Pre-mRNA processing
Translation of the mRNAs
into mitochondrial proteins
The assembly of
ribosomes and respiratory
complexes and are also
required for the targeting
and degradation of
organellar subunits.
42. 42
Alternative oxidase impacts the plant response to
biotic stress by influencing the mitochondrial
generation of reactive oxygen species
MARINA CVETKOVSKA & GREG C. VANLERBERGHE
Plant, Cell and Environment (2013) 36, 721–732
43. 43
Conductivity (ion leakage) of tobacco leaf (a,b) and bacterial proliferation in tobacco leaf
(c,d) at different times post-inoculation with P. syringae pv. maculicola (a,c) or pv.
phaseolicola (b,d).
44. 44
Laser-scanning confocal microscope images of mitochondrial O2- in
tobacco mesophyll cells at different times post-inoculation with P. syringae
pv. phaseolicola.
45. 45
Laser-scanning confocal microscope images of mitochondrial O2- in tobacco
mesophyll cells at different times post-inoculation with P. syringae pv.
maculicola.
46. 46
MnSOD (a), CuZnSOD (b) and FeSOD (c) activity in tobacco leaf at
different times post-inoculation with P. syringae pv. maculicola.
47. 47
H2O2 level in tobacco leaf at different times post-inoculation with P. syringae pv.
maculicola (a) or pv. phaseolicola (b).
48. 48
Laser-scanning confocal microscope images of
cellular NO in tobacco mesophyll cells at
different times post-inoculation with P. syringae
pv. maculicola
Laser-scanning confocal microscope
images of cellular ONOO- in tobacco
mesophyll cells at different times post-
inoculation with P. syringae pv. maculicola.
Mt genomes of seed plants are unusually large and vary in size at least in an order of magnitude. Much of these variations occur within a single family [10]. Seed plant mitochondrial genomes
Are for their very low mutation rate,
frequent uptake of foreign DNA by intracellular and horizontal gene transfer, and dynamic structure.
The evolving land plants have gained new mechanisms to facilitate more frequent gene exchanges between mt and cp genomes as well as between mt and nuclear genomes, which make mt genomes increase their sizes.
The ribosomes of mitochondria are different from those of chloroplasts and the cytoplasm, using a slightly different genetic code (a sequence of three bases that codes for a particular amino acid). Mitochondrial genomes code for all of the ribosomal RNAs found in mitochondria and for most of the tRNAs. Mitochondria make only a small number of proteins that are needed for electron transport and ATP production. The other proteins needed in mitochondria are coded by nuclear DNA, translated in the cytoplasm of the cell, then transported into the mitochondria. Plant mitochondria do not encode a full set of tRNAs, and some are imported from the cytoplasm.
One strand is called H strand Guanine rich 28 genes and the other is called L strand with 9 genes.
Gene organization of the rapeseed mitochondrial genome. Genes homologous to known protein-coding genes are indicated by red boxes. The blue
boxes represent rRNA genes. Pink boxes represent unidenti®ed ORFs longer than 150 amino acids. tRNA genes are represented by yellow boxes. Pseudo
genes including plastid gene segments are shown in pale green. orf222, a cms-related gene (20), is shown by a green box. Arrowheads indicate the direction
of reading frames. Dark green boxes located inside the circle represent 2 kb repeat regions. *From Heazlewood et al. (32); **From Sabar et al. (18).
Indeed, analyses of cDNAs in Arabidopsis
mitochondria suggest that few, if any of these ORFs are expressed as stable mRNAs
(Giege and Brennicke, 2001). Skovgaard et al., (2001) examined 34 bacterial
genomes and concluded that 30-90% of the annotated ORFs, particularly those that
were not present in other species, do not actually encode proteins. It is not
unreasonable to expect that most of the ORFs in the endosymbiotic mitochondrial
genomes, particularly those not conserved across taxa, are not expressed.
I to IV identify large
regions of homology between NA and NB.
Neither only wa352 nor only cox11 causes male sterility interaction of both this will causes male sterilty
. (A) The secondary structure of group II introns is characterized by six double-helical domains (I-VI), arising from a central hub. Each subdomain of DI and DII, DIII, DIV, DV, and DVI are outlined within the structure. All plant mitochondrial intron structures in angiosperms are classified as standard group IIA RNAs (Bonen, 2008). The conserved bulged-A residue in DVI, the exon-intron binding sites (i.e., EBS1/IBS1 and EBS2/IBS2), and tertiary interactions between different intron regions (indicated by roman letters) are shown in the model structure. The ORF encoding the MatR protein in nad1 intron 4 is encoded in intron domain IV. (B) Splicing pathway of the autocatalytic group II introns occurs by a two-step trans-esterification pathway. In the first step of the branching pathway, the 2'-OH group of the branch point adenosine nucleophilically attacks the phosphate at the 5'-splice site. The 5'-exon is released and the attacking adenosine adopts a 2',5'-branched structure that gives the intron a lariat form. Yet, in addition to this classical “branch-point” splicing reaction, some mitochondrial introns which lacks a DVI bulged A are excised as linear molecules which are generated by a “hydrolytic-pathway” of splicing (Li-Pook-Than and Bonen, 2006).
From above experiments we concluded that arabidnsis uncoupling protein containing transgenic plant are resistance againest abiotic stesses