1) The document discusses how silencing the chloroplast vesiculation (CV) gene in rice maintained photorespiration and nitrogen assimilation under elevated CO2 conditions.
2) It was found that CV-silenced rice plants had higher rates of photorespiration and expression of photorespiration genes compared to wild-type plants grown under elevated CO2.
3) The document also reports that OsCV interacts with the peroxisome biogenesis factor OsPEX11-1, and that CV silencing helped maintain higher numbers of chloroplasts, mitochondria, and peroxisomes, which are organelles involved in photorespiration.
Thisppy contains few solved questions of GATE 2009 examination along with explanations. This will be helpful for all those who are preparing for GATE, CSIR, UGC NET, etc. Complete set of questions along with answers and explanations can be viewed at http://purnasrinivas.weebly.com
Thisppy contains few solved questions of GATE 2009 examination along with explanations. This will be helpful for all those who are preparing for GATE, CSIR, UGC NET, etc. Complete set of questions along with answers and explanations can be viewed at http://purnasrinivas.weebly.com
Generation of MRP2 Efflux Transporter Knock-Out in HepaRG Cell Linemdmitc
MilliporeSigma's Jennifer Pratt recently presented a poster at the 2016 AAPS/ITC Transporter Workshop demonstrating the utility of HepaRG MRP2 Knockout cells for investigating drug-transporter interactions in the liver involving MRP2.
Sugars are molecules of fundamental importance for life on earth. Sugars act as primary carriers of captured energy from the sun. Sugars not only fuel cellular carbon and energy metabolism but also pay pivotal role as signaling molecules and sugar status modulates & coordinates internal regulators that govern growth and development. The genes involved in production of carbon from photosynthesis with its utilization, mobilization and allocation in various tissues at different developmental stages are highly regulated by sugars. In most plants, sucrose (Suc) is the end product of photosynthesis for translocation from the source to heterotrophic sinks through the sieve element/companion cell complex of the phloem.
1. Bio preservation of Red Cell Components 2. CULTURED RBCs 3. solvent plasmaDrShinyKajal
1. Bio preservation of Red Cell Components
2. CULTURED RBCs
3. Solvent plasma
Hypothermic storage
Cryopreservation
Lyophilization
Desiccated RBCs
Three major sources of cells are under consideration:
circulating stem and progenitor cells from adults or from cord blood
immortalized progenitors
pluripotent stem cells.
Immortalized Progenitors
LIQUID CULTURE METHODS- by the SED (stem cell factor (SCF), erythropoietin, and dexamethasone) and STIF cocktails (stem cell factor, thombopoietin, insulin-like growth factor-2, fibroblast growth factor-2)
ENUCLEATION- separation of extruded nuclei from cRBCs
SCALING UP- using cord blood CD34+ cells in bioreactors
and treated for 4 h with TNBP (tri-nitrobutylphosphate)solvent and with Triton X-100 detergent
Generation of MRP2 Efflux Transporter Knock-Out in HepaRG Cell Linemdmitc
MilliporeSigma's Jennifer Pratt recently presented a poster at the 2016 AAPS/ITC Transporter Workshop demonstrating the utility of HepaRG MRP2 Knockout cells for investigating drug-transporter interactions in the liver involving MRP2.
Sugars are molecules of fundamental importance for life on earth. Sugars act as primary carriers of captured energy from the sun. Sugars not only fuel cellular carbon and energy metabolism but also pay pivotal role as signaling molecules and sugar status modulates & coordinates internal regulators that govern growth and development. The genes involved in production of carbon from photosynthesis with its utilization, mobilization and allocation in various tissues at different developmental stages are highly regulated by sugars. In most plants, sucrose (Suc) is the end product of photosynthesis for translocation from the source to heterotrophic sinks through the sieve element/companion cell complex of the phloem.
1. Bio preservation of Red Cell Components 2. CULTURED RBCs 3. solvent plasmaDrShinyKajal
1. Bio preservation of Red Cell Components
2. CULTURED RBCs
3. Solvent plasma
Hypothermic storage
Cryopreservation
Lyophilization
Desiccated RBCs
Three major sources of cells are under consideration:
circulating stem and progenitor cells from adults or from cord blood
immortalized progenitors
pluripotent stem cells.
Immortalized Progenitors
LIQUID CULTURE METHODS- by the SED (stem cell factor (SCF), erythropoietin, and dexamethasone) and STIF cocktails (stem cell factor, thombopoietin, insulin-like growth factor-2, fibroblast growth factor-2)
ENUCLEATION- separation of extruded nuclei from cRBCs
SCALING UP- using cord blood CD34+ cells in bioreactors
and treated for 4 h with TNBP (tri-nitrobutylphosphate)solvent and with Triton X-100 detergent
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
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.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
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.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
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 .
2. Introduction
• During photorespiration, peroxisomal and mitochondrial
enzymes cooperate to convert glycolate, produced in the
chloroplast to glycerate to be recycled to the chloroplast
for the Calvin–Benson cycle. Glycolate oxidases, active
during photorespiration, contribute to the accumulation
of peroxisomal H2O2.
• Peroxisomal fission and proliferation are controlled by
the peroxisome biogenesis factors PEROXIN11 (PEX11)
protein family and several transcription factors.
FIG : CV-silenced rice maintained a higher
photorespiration under elevated CO2. (a) A
schematic representation of the photorespiratory
pathway of C3 plants. 1, rubisco small subunit
(RbcS); 2, 2-phosphoglycolate phosphatase
(PGP); 3, glycolate oxidase (GOX); 4, glutamate:
glyoxylate aminotransferase (GGAT); 5, glycine
decarboxylase (GCD); 6, serine: glyoxylate
aminotransferase (SHMT); 7, NAD+
hydroxypyruvate reductase (HPR); 8, glycerate
kinase (GLYK).
3. Photorespiration is - Antipphotosynthesis
Blue car – photosynthesis (fixation of C02) red car - Photorespiration
4. Silencing of OsCV (chloroplast vesiculation) maintained
photorespiration and N assimilation in rice plants grown under
elevated CO2
Kamolchanok Umnajkitikorn1,2 | Nir Sade3 | Maria del Mar Rubio Wilhelmi1 |
Matthew E. Gilbert1 | Eduardo Blumwald1
• High CO2 concentrations stimulate net photosynthesis by increasing CO2
substrate availability for Rubisco, simultaneously suppressing
photorespiration.
• They reported that silencing the chloroplast vesiculation (cv) gene in
rice increased source fitness, through the maintenance of chloroplast
stability and the expression of photorespiration-associated genes.
• At elevated CO2, CV-silenced rice plants maintained peroxisome
proliferation and photorespiration and displayed higher N assimilation than
wild-type plants.
• Co-immunoprecipitation of OsCV-interacting proteins suggested that,
similar to its role in chloroplast protein turnover.
5. • The nuclear gene chloroplast vesiculation (cv) encodes a protein
that plays a key role in the destabilization of the photosynthetic
apparatus during senescence and abiotic stress .
• Upon stress, CV interacts with thylakoid membrane-bound proteins
(i.e., PsbO1 in photosystem [PS]II and CYP20 in PSI) and stromal
proteins (i.e., chloroplastic glutamine synthetase, GS2), inducing
the formation of vesicles. CV-containing vesicles mobilize thylakoid
and stroma proteins to the vacuole for degradation.
• CV silencing was a valuable strategy to increase the tolerance of
plants to water deficit through the maintenance of chloroplast
integrity.
Introduction
6. OsCV silencing induced grain yield increase and high seed
protein content in rice plants grown under elevated CO2
Image source : Kamolchanok Umnajkitikorn1,2 | Nir Sade3
• High atmospheric CO2 concentrations
inhibit both photorespiration and shoot
nitrate assimilation, with the associated
decrease in plant protein contents .
• High CO2 enhanced plant growth in
a similar manner in all genotypes.
Elevated CO2 enhanced grain yield
production in both WT and CV-
silenced plants;
Under ambient and elevated CO2.
Growth
7. OsCV silencing induced higher photorespiration under
elevated CO2
• When grown under elevated CO2, CV-silenced rice plants displayed
higher Rubisco oxygenation (Vo) than WT plants.
• The expression levels of genes encoding Rubisco small subunit
(RbcS); 2-phosphoglycolate phosphatase (PGP), glycolate oxidase
(GOX), were significantly higher than WT grown under elevated CO2.
Of the photorespiration pathway-associated metabolites tested,
glycolate, serine, glycerate, and malic acid were higher in CV-silenced
plants than in WT plants.
• calculated the glycine:serine ratio resulting significantly higher in WT
compare with CV silenced plants under high CO2 conditions.
8. (b) photorespiration rate (Vo) of wild-type (WT)
and RNAi-OsCV plants under ambient and
elevated CO2
(Relative expression of selected transcripts associated
with photorespiration (1–8 as shown in panel a) of WT and
RNAi-OsCV plants under elevated CO2)
OsCV silencing induced higher photorespiration
under elevated CO2
Rubisco small subunit (RbcS); 2-phosphoglycolate phosphatase (PGP),
glycolate oxidase (GOX), were significantly higher than WT grown
under elevated CO2. Of the photorespiration pathway-associated
metabolites tested, glycolate, serine, glycerate, and malic acid were
higher in CV-silenced plants than in WT plants.
9. (d) Selected metabolite contents of WT
and RNAi-OsCV plants under elevated
CO2. The dashed line represents the
value of each metabolite under ambient
conditions.
(e) Glycine:serine ratio of
WT and RNAi- OsCV
plants grown under
elevated CO2
• However, the yield increase
was significantly higher in
CV-silenced plants than in
WT Seed protein contents
decreased in WT plants
under elevated CO2,
• whereas it remained
constant in CV-silenced
plants.
OsCV silencing induced higher photorespiration
under elevated CO2
10. OsCV interacts in vivo with OsPEX11 (peroxisome biogenesis
factor 11)
• Identified putative CV-interacting proteins by coimmunoprecipitation and subsequent MS-
based identification of the interacting proteins.
• BiFC (Bimolecular fluorescence complementation )was used to confirm the OsCV-
OsPEX11 interaction.
• The transient expression of the fusion genes OsCVSCFPC and OsPEX11-VenusN in N.
benthamiana resulted in BiFC fluorescence (Figures 3b–d), confirming the in vivo interaction
between OsCV and OsPEX11-1.
• In addition, OsCV was enriched in both at chloroplast thylakoid membranes and peroxisomes
These results indicated the interaction of OsCV with PEX11 in peroxisomes and a role for
OsCV in PEX11 turnover.
11. • The mechanism of OsCV affect
photorespiration , identified CV
interacting proteins by
immunoprecipitation ,
• OsCV has a role in the mobilization
of the peroxisomal biogenesis
factor 11 (OsPEX11-1) from
peroxisome to vacuoles.
BiFC signals obtained 1 day after infiltration. Most of
the signals overlapped with the peroxisome (blue
arrows)
OsCV interacts in vivo with OsPEX11(peroxisome
biogenesis factor 11)
12. OsCV interacts in vivo with OsPEX11(peroxisome
biogenesis factor 11)
• The transient expression of the fusion genes OsCV-SCFPC and OsPEX11-
VenusN in N. benthamiana resulted in BiFC fluorescence (SCFPC and VenusN
were fused at the C-terminus of OsCV and OsPEX11-1, respectively. (Nicotiana
benthamiana.)
• The colocalization of the BiFC complex and mCherry-SKL fluorescence
indicated the peroxisomal localization of the BiFC complex.
• To assess whether, similar to other protein degradation pathways, the
OsCV/OsPEX11-1 complex was mobilized to the vacuoles, the BiFC constructs
were transiently coexpressed with Rab2a-RFP.
• The CV-PEX11 BiFC complex was transported through the endomembrane
system to the PVC and vacuoles, as indicated by its colocalization with RabF2a-
RFP after 2–3 days.
13. (c) BiFC signals obtained 2 to 3 days
after infiltration. Signals overlapped
with chloroplasts and the prevacuolar
compartment marker RabF2a-RFP
Transiently coexpressed CV-CFP
together with PEX11-YFP in N.
benthamiana leaves. Cells that
coexpressed both CV-CFP and
PEX11-YFP showed the
colocalization of both proteins at
peroxisomes
d) BiFC signals obtained 4 days after
infiltration. Signals overlapped with the
vacuolar marker VAMP711-RFP.
OsCV interacts in vivo with OsPEX11 (peroxisome
biogenesis factor 11)
14. (e–f) Coimmunodetection of CV-GFP and OsGOX
(peroxisome marker) in peroxisomes.
(e) EST-CV-GFP transgenic plants were
induced by 50-μM β-estradiol, labelled
with anti-GFP mouse (10-nm gold
particles, red arrows) and anti-GOX
rabbit (20-nm gold particles, yellow
arrows) and observed by
immunolabeling transmission electron
microscopy. Red arrows indicate
OsCV presence in both chloroplast and
peroxisomes. Black and white squares
indicate CV localization in peroxisomes.
(f) A higher magnification of the area
from black square in (e)
OsCV interacts in vivo with OsPEX11
(peroxisome biogenesis factor 11)
15. • Chloroplasts, mitochondria, and peroxisomes cell organelles associated with photorespiration.
WT plants grown under elevated C02 Shows decrease in 3 organelles. whereas CV-silenced
plants maintained the same numbers of organelles
• OsCV localized to the chloroplast and to the peroxisomes Natural or stress-induced senescence
activated CV expression CV migrated to the chloroplasts and penetrated the chloroplast
envelope while disrupting the chloroplast integrity.
• It inserted into the thylakoid membranes, mediating the formation of vesicles that were
trafficked to the vacuole.
• CV-silenced rice plants maintained catalase activity under elevated CO2, whereas WT plants
displayed a 28% decrease in activity . These results indicated that consistent with the physical
interaction of OsCV with OsPEX11-1, CV associated with peroxisomes under elevated CO2,
CV expression induced a decline in number of
chloroplasts, mitochondria, and peroxisomes
16. CV expression induced a decline in number of
chloroplasts, mitochondria, and peroxisomes
CV silencing contributed to more coherence of organelles necessary for
photorespiration and detoxification of H2O2.
TEM Showing ultrastructure (a) and RNAi-OsCV (b) leaf mesophyll cells,
under elevated CO2. Organelles were labeled as M, mitochondria; P,
peroxisomes
c) Numbers of organelles involved in
photorespiration of WT and RNAi-OsCV leaf
mesophyll cells under elevated CO2 as
observed by transmission electron microscopy
17. CV expression induced a decline in number of
chloroplasts, mitochondria, and peroxisomes
(d–f)Catalase activity (d), H2O2 content (e) and MDA content (f) of WT and RNAi-
OsCV leaves under elevated CO2
18. Silencing CV facilitated N assimilation in plants grown
under elevated CO2
CV-silenced rice maintained N metabolism under elevated
CO2
(a, d) Relative expression of nitrate reductase (NR) and
chloroplastic glutamine synthetase 2 (GS2) of wild type
(WT) and RNAi-OsCV plants under elevated CO2
(b, e) NR activity and GS activity of WT and
RNAi-OsCV plants under elevated CO2.
19. Silencing CV facilitated N assimilation in plants grown
under elevated CO2
(b, e) NR activity and GS activity of WT and RNAi-OsCV
plants under elevated CO2
f)Relative intensity of bands appearing on Wester
blots of NR and GS.
20. OsCV-silenced enhanced nitrogen assimilation, total protein content, and amino acid content under elevated CO2
compared with
plants grown at ambient CO2. (a) δ15N of wild type (WT) and RNAi-OsCV, under elevated CO2 conditions. Values are
the mean ± standard error (SE) (n = 4–5). The dashed lines represent the average δ15N contents under ambient
conditions. (b) Total protein contents of WT and RNAi-OsCV plants under ambient and elevated CO2 conditions.
Values are the mean ± SE (n = 4). (c) Amino acid contents of WT and RNAi-OsCV plants under elevated CO2. The
dashed lines represent the average amino acid contents under ambient conditions. Values are the mean ± SE (n = 4).
The asterisks indicate significant differences from WT for each amino acid by Student's t-test (p ≤ .05)
Silencing CV facilitated N assimilation in plants grown
under elevated CO2
21. SUMMARY
• High CO2 stimulate net photosynthesis by increasing CO2 substrate
availability for Rubisco, simultaneously suppressing photorespiration.
• silencing the chloroplast vesiculation (cv) gene in rice increased source
fitness, chloroplast stability and the expression of photorespiration-
associated genes.
• CV silencing might be a viable strategy to improve the effects of high
CO2 on grain yield and N assimilation in rice.
• Under elevated CO2, OsCV expression was induced, and OsCV was
targeted to peroxisomes where it facilitated the removal of OsPEX11-1
from the peroxisome and delivered it to the vacuole for degradation., the
decreased catalase activity and the increased H2O2 content in wild-type
plants under elevated CO2.
• At elevated CO2, CV-silenced rice plants maintained peroxisome