AS07 239, anti-Toc159, translocon at the outer envelope membrane of chloroplasts, Toc-complex, TOC-complex, GTPase, Chloroplast protein import component Toc159, Toc 159 antibody, Q9LKR1Toc159 is located in the outer chloroplast membrane and part of of the
We have shown that chloroplasts of the green algae, C. reinhardtii, are capable of accumulating fully functional immunotoxin proteins that consist of an antibody-binding domain targeting the B-cell surface antigen CD22 and the PE40 toxin domain of exotoxin A. We produced two different types of immunotoxins, single chain and dimeric, and both accumulated as soluble functional proteins within algal chloroplasts. Producing a eukaryotic toxin in a eukaryotic cell was possible because chloroplasts have a prokaryotic-like translational apparatus that is resistant to the toxin and because proteins produced in the chloroplast stay in the chloroplast. A single PE40 molecule escaping the chloroplast should be able to inhibit protein translation in the algal cytosol, resulting in cell death. The survival of algae producing the immunotoxins demonstrates that chloroplasts sequester chloroplast-produced proteins completely within the chloroplast. In addition to sequestering the toxin, allowing the production ...
In this study, we showed that PI4K inhibition increased the rate of chloroplast division. Two kinds of PI4K inhibitor treatments and downregulation of PI4K expression similarly increase the number of chloroplasts, indicating that PI4P is a negative regulator of chloroplast division. Inhibition of PI4K caused an increase of chloroplast division in parallel with an increase in the amount of DRP5B localized on the surface of chloroplasts (Figures 5B and 5C). These results suggest that the binding of PI4P to PDV1 changes the interaction between PDV1 and DRP5B. Decrease of PI4P in envelope membranes probably causes increases in the binding affinity of PDV1 for DRP5B or inhibits the dissociation of DRP5B from chloroplasts. As a result, the recruitment of DRP5B to chloroplasts increases and may enhance the rate of chloroplast division. In addition, the total protein level of DRP5B was increased by the PAO treatment (Figure 5B). The increase in DRP5B recruited to chloroplasts suggests that the ...
Based on our phylogeny and character state reconstructions, there was one probable origin of short-term chloroplast retention in the last common ancestor of the Plakobranchoidea, and four independent origins of long-term retention. No species in the Oxynoacea and Limapontioidea were able to maintain photosynthetic activity, based on PAM measurements. Functional chloroplast retention was not detected in five oxynoacean species representing the basal shelled sacoglossans (Table 3). In species with no functional retention, chloroplasts are phagocytosed by digestive glandular cells and rapidly disintegrate [62, 63]. Clark and Busacca [64] concluded that Oxynoe retains chloroplasts because they were able to isolate chlorophyll from slugs, but they did not detect net fixation of CO2. We measured high ground fluorescence in oxynoaceans but very low yield values, indicating free chlorophyll but no functional chloroplasts.. Similarly, all limapontioidean species except Costasiella cf. kuroshimae had ...
The TIC and TOC complexes are translocons located in the chloroplast of a eukaryotic cell, that is, protein complexes that facilitate the transfer of proteins in and out through the chloroplasts membrane. The TIC complex (translocon on the inner chloroplast membrane) is located in the inner envelope of the chloroplast. The TOC complex (translocon on the outer chloroplast membrane) is located in the outer envelope of the chloroplast. It transports proteins that are synthesized in the cytoplasm across the chloroplasts membrane. This protein complex is functionally similar to the TOM/TIM Complex located on the outer and inner membranes of the mitochondria, in the sense that it too transports proteins across multiple membranes and into the lumen of an organelle. Both complexes (TOC/TIC) are GTPases, that is, they must both hydrolyze GTP in order to power the translocation. The chloroplast also harnesses the power of an electrochemical gradient using protons. The gradient is only used to power ...
Successful import of hundreds of nucleus-encoded proteins is essential for chloroplast biogenesis. The import of cytosolic precursor proteins relies on the Toc- (translocon at the outer chloroplast membrane) and Tic- (translocon at the inner chloroplast membrane) complexes. In |i|Arabidopsis thaliana|/i|, precursor recognition is mainly mediated by outer membrane receptors belonging to two gene families: Toc34/33 and Toc159/132/120/90. The role in import and precursor selectivity of these receptors has been intensively studied, but the function of Toc90 still remains unclear. Here, we report the ability of Toc90 to support the import of Toc159 client proteins. We show that the overexpression of Toc90 partially complements the albino knockout of Toc159 and restores photoautotrophic growth. Several lines of evidence including proteome profiling demonstrate the import and accumulation of proteins essential for chloroplast biogenesis and functionality. Infanger, Sibylle; Bischof, Sylvain;
DnaK (chloroplast stromal chaperone) antibody, AS07 270, CHLREDRAFT_154866DnaK, chloroplast stromal chaperone, heat shock protein 70, hsp70
Figure 14 Phase contrast fluorescence microscopy of Cry2A transgenic plants with transit peptide. A = DAPIblue fluorescence. B = FITC green fluorescence. C = Chloroplast auto-fluorescence red. D = Merged image of A, B and C. Yellow color is produced where green and red fluorescence occurred at the same place i.e. Cry2A inside chloroplasts.. Discussion. Chloroplast targeted expression of the Bt gene holds great potential for incorporating vital agronomic traits into plants. High Bt gene levels in chloroplasts permits plants to generate large quantities of crystal proteins. In the present study, two insecticidal genes, Cry1Ac and Cry2A, along with a chloroplast transit peptide were cloned in a PBI-121 vector and transformed into cotton variety MNH-786. Cry1Ac and Cry2A were selected because of their unique qualities, i.e., high expression levels and lack of competition for receptors among them.. The present study highlights the importance of cloning genes with transit peptides to demonstrate ...
The import of nucleus-encoded proteins into chloroplasts is mediated by translocon complexes in the envelope membranes. A component of the translocon in the outer envelope membrane, Toc34, is encoded in Arabidopsis by two homologous genes, atTOC33 and atTOC34. Whereas atTOC34 displays relatively uniform expression throughout development, atTOC33 is strongly upregulated in rapidly growing, photosynthetic tissues. To understand the reason for the existence of these two related genes, we characterized the atTOC33 knockout mutant ppi1. Immunoblotting and proteomics revealed that components of the photosynthetic apparatus are deficient in ppi1 chloroplasts and that nonphotosynthetic chloroplast proteins are unchanged or enriched slightly. Furthermore, DNA array analysis of 3292 transcripts revealed that photosynthetic genes are moderately, but specifically, downregulated in ppi1. Proteome differences in ppi1 could be correlated with protein import rates: ppi1 chloroplasts imported the ...
Chloroplasts are organelles found in plant cells and eukaryotic algae which conduct photosynthesis. Chloroplasts are similar to mitochondria but are found only in plants. Both organelles are surrounded by a double membrane with an intermembrane space; both have their own DNA and are involved in energy metabolism; and both have reticulations, or many foldings, filling their inner spaces. Chloroplasts convert light energy from the sun into ATP through a process called photosynthesis. Chloroplasts are one of the forms a plastid may take, and are generally considered to have originated as endosymbiotic cyanobacteria. In green plants chloroplasts are surrounded by two lipid bilayer membranes, now thought to correspond to the outer and inner membranes of the ancestral cyanobacterium. The genome is considerably reduced compared to that of free-living cyanobacteria, but the parts that are still present show clear similarities. It is interesting to note that in some algae, chloroplasts seem to have ...
Chloroplasts change their position in a cell in response to environmental light conditions (Wada et al., 1993, 2003). Low-fluence rate light induces movement of chloroplasts toward the irradiated area, resulting in chloroplast accumulation at the front face of the cell (accumulation response). Conversely, under high-fluence rate light, chloroplasts move to the anticlinal wall of the cell to avoid photodamage (avoidance response; Kasahara et al., 2002). Chloroplast photorelocation movement is found in several photosynthetic plant species, including yellow and green algae, mosses, ferns, and flowering plants. In most plant species, chloroplast movement is induced by irradiation with blue light, although it is also induced by red light in some cryptogam plants (Wada et al., 1993, 2003). The flowering plant Arabidopsis (Arabidopsis thaliana) has two types of blue-light photoreceptor, cryptochromes (cry1 and cry2) and phototropins (phot1 and phot2). Cryptochrome is a flavoprotein similar to the ...
TY - JOUR. T1 - The identification and localization of 33 pea chloroplast transcription initiation sites. AU - Woodbury, Neal. AU - Dobres, Michael. AU - Thompson, William F.. PY - 1989/12/1. Y1 - 1989/12/1. N2 - We have used a novel approach to produce a comprehensive transcription initiation map of the pea chloroplast genome. Sites were mapped by measuring the ability of DNA probes to protect 5′ ends of transcripts that have been capped in vitro. Using this approach, at least 33 probes appear to contain one or more transcription start sites. A more precise location of some of these sites was obtained by hybrid selecting certain of these RNAs and determining their size both before and after RNase treatment. We have found at least one initiation site in front of every chloroplast gene cluster for which appropriate clones were available. In addition, we have found initiation sites within gene clusters previously shown to be co-transcribed. In one such case, we were able to locate a ...
Toc34 is an integral protein in the outer chloroplast membrane thats anchored into it by its hydrophobic[48] C-terminal tail.[38][46] Most of the protein, however, including its large guanosine triphosphate (GTP)-binding domain projects out into the stroma.[46]. Toc34s job is to catch some chloroplast preproteins in the cytosol and hand them off to the rest of the TOC complex.[38] When GTP, an energy molecule similar to ATP attaches to Toc34, the protein becomes much more able to bind to many chloroplast preproteins in the cytosol.[38] The chloroplast preproteins presence causes Toc34 to break GTP into guanosine diphosphate (GDP) and inorganic phosphate. This loss of GTP makes the Toc34 protein release the chloroplast preprotein, handing it off to the next TOC protein.[38] Toc34 then releases the depleted GDP molecule, probably with the help of an unknown GDP exchange factor. A domain of Toc159 might be the exchange factor that carry out the GDP removal. The Toc34 protein can then take up ...
Toc34 is an integral protein in the outer chloroplast membrane thats anchored into it by its hydrophobic[52] C-terminal tail.[42][50] Most of the protein, however, including its large guanosine triphosphate (GTP)-binding domain projects out into the stroma.[50] Toc34s job is to catch some chloroplast preproteins in the cytosol and hand them off to the rest of the TOC complex.[42] When GTP, an energy molecule similar to ATP attaches to Toc34, the protein becomes much more able to bind to many chloroplast preproteins in the cytosol.[42] The chloroplast preproteins presence causes Toc34 to break GTP into guanosine diphosphate (GDP) and inorganic phosphate. This loss of GTP makes the Toc34 protein release the chloroplast preprotein, handing it off to the next TOC protein.[42] Toc34 then releases the depleted GDP molecule, probably with the help of an unknown GDP exchange factor. A domain of Toc159 might be the exchange factor that carry out the GDP removal. The Toc34 protein can then take up ...
Chloroplasts originated from an endosymbiotic event in which a free-living cyanobacterium was engulfed by an ancestral eukaryotic host. During evolution the majority of the chloroplast genetic information was transferred to the host cell nucleus. As a consequence, proteins formerly encoded by the chloroplast genome are now translated in the cytosol and must be subsequently imported into the chloroplast. This process involves three steps: (i) cytosolic sorting procedures, (ii) binding to the designated receptor-equipped target organelle and (iii) the consecutive translocation process. During import, proteins have to overcome the two barriers of the chloroplast envelope, namely the outer envelope membrane (OEM) and the inner envelope membrane (IEM). In the majority of cases, this is facilitated by two distinct multiprotein complexes, located in the OEM and IEM, respectively, designated TOC and TIC. Plants are constantly exposed to fluctuating environmental conditions such as temperature and light ...
Christoph Benning MSU Foundation Professor; Director, Plant Research Laboratory, Michigan State University Research: Biosynthesis of lipids in photosynthetic membranes, lipid trafficking phenomena involving chloroplasts, engineering of crops and algae for biodiesel production. Lipid Assembly, Remodeling, and Transport to Build and Protect the Photosynthetic Membrane Photosynthesis sustains most life forms on earth providing food, feed, fuels, organic chemicals, and the oxygen in the atmosphere. In plants and algae, the photosynthetic membrane inside chloroplasts mediates the conversion of light into chemical energy. Specific polar lipids consisting of fatty acyl groups attached to glycerol with a polar head group are key components of the photosynthetic membrane. Fatty acid biosynthesis occurs in the chloroplasts, and polar lipids destined for the photosynthetic membrane are assembled at both chloroplast envelope membranes and the endoplasmic reticulum. Lipid precursors have to be shuttled between
Plastocyanin is a nuclear-encoded chloroplast thylakoid lumen protein that is synthesized in the cytoplasm with a large N-terminal extension (66 amino acids). Transport of plastocyanin involves two steps: import across the chloroplast envelope into the stroma, followed by transfer across the thylakoid membrane into the lumen. During transport the N-terminal extension is removed in two parts by two different processing proteases. In this study we examined the functions of the two cleaved parts, C1 and C2, in the transport pathway of plastocyanin. The results show that C1 mediates import into the chloroplast. C1 is sufficient to direct chloroplast import of mutant proteins that lack C2. It is also sufficient to direct import of a nonplastid protein and can be replaced functionally by the transit peptide of an imported stromal protein. C2 is a prerequisite for intraorganellar routing but is not required for chloroplast import. Deletions in C2 result in accumulation of intermediates in the stroma or ...
How do plant cells get rid of chloroplasts that are not working as they should? Woodson et al. describe a chloroplast quality-control pathway that allows for the selective elimination of individual chloroplasts. Damage by reactive oxygen species during photosynthesis is recognized by a ubiquitin ligase, which marks out damaged chloroplasts for degradation. The findings reveal how cells balance inherently stressful energy production with organelle turnover.. J. D. Woodson, M. S. Joens, A. B. Sinson, J. Gilkerson, P. A. Salomé, D. Weigel, J. A. Fitzpatrick, J. Chory, Ubiquitin facilitates a quality-control pathway that removes damaged chloroplasts. Science 350, 450-454 (2015). [Abstract] [Full Text] ...
During the course of NH4+ (or NO2-)-plus-alpha-oxoglutarate-dependent O2 evolution in spinach (Spinacia oleracea) chloroplasts, glutamate was continuously excreted out of the chloroplasts. Under these conditions, for each molecule of NO2- or NH4+ which disappeared, one molecule of glutamate accumulated in the medium and the concentration of glutamate in the stroma space was maintained constant. SO4(2-) (or SO3(2-) behave as inhibitors of NH4+ incorporation into glutamate by intact chloroplasts. This considerable inhibition of glutamate synthesis by SO4(2-) was correlated with a rapid decline in the stromal Pi concentration. The reloading of stromal Pi with either external Pi or PPi4- relieved SO4(2-)-induced inhibition of glutamate synthesis by intact chloroplasts. It was concluded that SO4(2-) induced a rapid efflux of stromal Pi out of the chloroplast, leading to a limitation of ATP synthesis and therefore to an arrest of ATP-dependent glutamine synthetase functioning. ...
The chloroplast is the site of photosynthesis that enabled and sustains aerobic life on Earth. Chloroplasts are relatively large organelles with a diameter of ~5 μm and width of ~2.5 μm, and so can be readily analysed by electron microscopy. Each chloroplast is enclosed by two envelope membranes, which encompass an aqueous matrix, the stroma and the thylakoids. Components of stroma include starch granules and plastoglobuli, which can be observed by electron microscopy. And the thylakoids consist of stromal thylakoid, granal thylakoid and as well as granum (a stack of thylakoids). These structure components are quite sensitive to developmental changes and environmental variations, such as drought, salinity, cold, high temperature and others. Transmission electron microscopy (TEM) is a powerful technique for monitoring the effects of various changing parameters or treatments on the development and differentiation of these important organelles. Here we describe a reliable method for the analysis of
We present a neural network based method (ChloroP) for identifying chloroplast transit peptides and their cleavage sites. Using cross-validation, 88% of the sequences in our homology reduced training set were correctly classified as transit peptides or nontransit peptides. This performance level is well above that of the publicly available chloroplast localization predictor PSORT. Cleavage sites are predicted using a scoring matrix derived by an automatic motif-finding algorithm. Approximately 60% of the known cleavage sites in our sequence collection were predicted to within +/-2 residues from the cleavage sites given in SWISS-PROT. An analysis of 715 Arabidopsis thaliana sequences from SWISS-PROT suggests that the ChloroP method should be useful for the identification of putative transit peptides in genome-wide sequence data. The ChloroP predictor is available as a web-server at http://www.cbs.dtu.dk/services/ChloroP/.. ...
Post-translational protein methylation was investigated in Pisum sativum chloroplasts. Intact pea chloroplasts were incubated with ({sup 3}H-methyl)-S-adenosylmethionine under various conditions. The chloroplasts were then separated into stromal and thylakoid fractions and analyzed for radioactivity transferred to protein. Light enhanced the magnitude of labeling in both fractions. One thylakoid polypeptide with an apparent molecular mass of 43 kDa was labeled only in the light. Several other thylakoid and stromal proteins were labeled in both light and dark-labeling conditions. Both base-labile methylation, carboxy-methylesters and base-stable groups, N-methylations were found. Further characterization of the methyl-transfer reactions will be presented. ...
Plant cells contain an internal clock (the circadian clock), which is able to regulate cellular processes so that they occur at the optimal time of day, causing a big increase in plant productivity. As chloroplasts are the site of photosynthesis, their function is highly dependent on the daily changes in light environment.. It is thought that chloroplasts were originally free-living organisms that were incorporated into the cells of plants very early in plant evolutionary history. A result of this is that chloroplasts have retained some of the cellular machinery required to produce proteins from their own chloroplast DNA. An essential part of this machinery are sigma factors, and in present-day plants, they are encoded for by the cells nuclear DNA.. The researchers were able to show that the production of sigma factors is controlled by the plants clock. This enables the nuclear DNA to regulate the activity of chloroplast genes, and ensure that the production of proteins essential for ...
TY - JOUR. T1 - Chloroplasts are partially mobilized to the vacuole by autophagy. AU - Ishida, Hiroyuki. AU - Yoshimoto, Kohki. PY - 2008/10/1. Y1 - 2008/10/1. N2 - Excluding the central vacuole, chloroplasts constitute the largest compartment within the leaf cells of plants and contain approximately 80 percent of the total leaf nitrogen, mainly as proteins. Much of this nitrogen is allocated to the carbon-fixing enzyme in photosynthesis, Rubisco. During senescence, plants can mobilize nitrogen from chloroplasts in older leaves to other organs, such as developing seeds. Whereas bulk degradation of the cytosol and organelles in plants occurs by autophagy, the role of autophagy in the degradation of chloroplast proteins is still unclear. We have recently demonstrated that stroma-targeted green fluorescent protein (GFP), DsRed, and GFP-labeled Rubisco can be mobilized to the vacuole of living cells via Rubisco-containing bodies, in an ATG gene-dependent manner. Our results indicate the presence of ...
A plastid is an organelle that is commonly found in photosynthetic plants. Plastids are of different types depending on the presence of the pigment and metabolic functions. They may be chloroplasts, chromoplasts, and leucoplasts. A chloroplast is a plastid that contains high amounts of green pigment, chlorophyll. The chlorophyll pigments may be chlorophyll a, chlorophyll b, chlorophyll c, chlorophyll d, and chrlorophyll f. Chlorophyll a is present in all chloroplasts. Other pigments that may be present (particularly in algal cells) are carotenoids and phycobilins. The chloroplast has at least three membrane systems: outer membrane, inner membrane, and thylakoid system. The thylakoids are disk-shaped structures that function as the site of photosynthesis. It is because embedded in the thylakoid membrane is the antenna complex consisting of proteins, and light-absorbing pigments, including chlorophyll (the green pigment) and carotenoids. The chlorophyll is capable of absorbing light energy for use ...
Word Scramble - English word CHLOROPLASTS: words that start with chloroplasts, words that end with chloroplasts, anagrams of chloroplasts, how to spell chloroplasts!, Words with Friends, Scrabble
Numerous studies show ramifications of abscisic acid solution (ABA) about nuclear genes encoding chloroplast-localized proteins. It repressed transcription from the chloroplast phage-type T0070907 and bacteria-type RNA polymerases and reduced transcript degrees of most looked into chloroplast genes significantly. ABA didnt repress the transcription of and some other genes as well as increased mRNA amounts under certain circumstances. The ABA results on chloroplast transcription had been even more pronounced in basal vs. apical leaf sections and improved by light. Simultaneous software of cytokinin (22 μM 6-benzyladenine) reduced the ABA results on chloroplast gene manifestation. These data show that ABA impacts the manifestation of chloroplast genes differentially and factors to a job of ABA in the rules and coordination of the actions of nuclear and chloroplast genes coding for protein with features in photosynthesis. (L.) nucleus-encoded plastid RNA polymerase (NEP) plastid-encoded plastid ...
In this study, we produced selective images of photosystems in plant chloroplasts in situ. We used a spectroimaging microscope, equipped with a near-infrared (NIR) laser that provided light at wavelengths mainly between 800 and 830 nm, to analyze chlorophyll autofluorescence spectra and images from chloroplasts in leaves of Zea mays at room temperature. Femtosecond laser excitation of chloroplasts in mesophyll cells revealed a spectral shape that was attributable to PSII and its antenna in the centers of grana spots. We found that a continuous wave emitted by the NIR laser at a wavelength as long as 820 nm induced chlorophyll autofluorescence with a high contribution from PSI through a one-photon absorption mechanism. A spectral shape attributable to PSI and its antenna was thus obtained using continuous wave laser excitation of chloroplasts in bundle sheath cells. These highly pure spectra of photosystems were utilized for spectral decomposition at every intrachloroplast space to show ...
Chloroplasts are organelles that take light energy and convert it into chemical energy. A chloroplast has a double membrane, the inner and outer membranes. The inner thylakoid membrane traps the light energy. Inside the inner membrane are stacks of grana, and surrounding the grana is a fluid known as stroma. Chloroplasts, which are contained in chlorophyll, contain the green pigment chlorophyll, which traps light energy and make leaves and stems green. The chemical energy that is captured by the chloroplasts is stored in sugar molecules until they are broke down. ...
Chloroplasts have been discovered to be fierce transformers, warriors. Yes, like Bumble Bee and Optimus Prime. Unless you had an unorthodox elementary education in science, you learned about the innocent chloroplast. To refresh your memory, chloroplasts are organelles of plant cells and conduct photosynthesis for the plant. In their everyday life, chloroplasts are a cornerstone…
Berkeley - As biologists try to tease out the finer details of the green plant family tree, one key may lie in the cellular organelle - the chloroplast - that makes green plants green. As the photosynthetic factory of the plant cell, the chloroplast contains its own complement of genes distinct from the comparably sized mitochondrial genome in the energy center of the cell or the much larger genome in the cell nucleus. The chloroplast genome can be more informative in some ways than the complete nuclear genome, and easier to analyze than plant mitochondrial DNA, said Brent Mishler, professor of integrative biology at the University of California, Berkeley, and director of the Jepson and University Herbaria. Mishler is one of nine principal investigators on a new project, supported by $3 million over five years from the National Science Foundation, to isolate and sequence chloroplast and mitochondrial genomes from 50 to 100 representative plants, drawing on the expertise of the U.S. Department ...
The locations of polymorphic sites between chloroplast genomes of 93-11 and PA64S were documented according to the nucleotide order of the 93-11 chloroplast DNA sequence. The oblique line (/) separates the corresponding variations of codons and amino acids in the involved genes between 93-11 and PA64S. Genes were annotated according to the published chloroplast genome (Hiratsuka, et al., 1989). The gene symbols in this table are as follows: ORF, open reading frame; rsp16, ribosomal protein S16; psbk, PSII K protein; rpoC2, RNA polymerase β′-subunit-2; atpA, ATPase α-subunit; rbcL, ribulose 1,5-bisphosphate carboxylase/oxygenase large subunit; rp120, ribosomal protein L20; psbB, PSII 47-kD protein; rp116, ribosomal protein L16; rps3, ribosomal protein S3; and ndhF, NADH dehydrogenase ND5. ...
Showed a moderately decreased synthesis rate for the chloroplast-encoded proteins, which may account for the accumulation of photosynthetic proteins (Figure
Introduction. How ATP is produced in both the chloroplast and mitochondria Introduction: Living organisms use it as a free-energy donor to supply free energy for three major purposes: muscular contraction and other cellular movements, the active transport of molecules and ions, and the synthesis of proteins. ATP is not a long-term storage form of energy - is an immediate donor of energy. Most ATP is consumed within a minute ofbeing produced. The turnover of ATP is very high . ATP Generation in Mitochondria and Chloroplasts: ATP generation is driven by the electrochemical gradient of protons (the proton motive force) that exists in both mitochondria and chloroplasts. However, the mechanisms in each organelle are different when compared in detail, as will be considered later. In both chloroplasts and mitochondria the driving force behind ATP synthesis is the proton motive force that exists between two cellular compartments. This force is produced by the electrochemical gradient for H+ across the ...
(figure) Figure 1.7 A mature and functional chloroplast in an immature leaf of bean (Phaseolus vulgaris) with an extensive network of photosynthetic membranes (thylakoids), parts of which are appressed into moderate granal stacks, and suspended in a gel-like matrix (stroma).The chloroplast contains a pair of starch grains (S) encapsulated in a doub
This study reveals light-dependent associations of PEP and pTAC3 with chloroplast DNA in vivo using cpChIP assays. ChIP assays have been widely used to detect specific binding sites for transcription factors (29), distribution patterns of several modified histones (30), and trafficking of RNAP and its associated proteins on genomic DNA (31). In chloroplasts, a few studies have shown the association of endogenous (Whirly1) and recombinant (LacI) transcription factors with chloroplast promoters in vivo by using ChIP assays (32, 33). However, in vivo dynamics of chloroplast RNA polymerases and/or their associated proteins have not been directly characterized experimentally. Unlike cyanobacteria, the chloroplasts of higher plants have two types of RNA polymerase, PEP and NEP. Transcriptome analyses of PEP- or NEP-deficient mutants and in vitro transcription analyses using isolated PEP and NEP have shown that PEP and NEP preferentially initiate transcription from bacterial-type and phage-type ...
Plant cotyledons are a tissue that is particularly active in plastid gene expression in order to develop functional chloroplasts from pro-plastids, the plastid precursor stage in plant embryos. Cotyledons, therefore, represent a material being ideal for the study of composition, function and regulation of protein complexes involved in plastid gene expression. Here, we present a pilot study that uses heparin-Sepharose and phospho-cellulose chromatography in combination with isoelectric focussing and denaturing SDS gel electrophoresis (two-dimensional gel electrophoresis) for investigating the nucleotide binding proteome of mustard chloroplasts purified from cotyledons. We describe the technical requirements for a highly resolved biochemical purification of several hundreds of protein spots obtained from such samples. Subsequent mass spectrometry of peptides isolated out of cut spots that had been treated with trypsin identified 58 different proteins within 180 distinct spots. Our analyses indicate a high
A two-membrane system, or envelope, surrounds plastids. Because of the integration of chloroplast metabolism within the plant cell, the envelope is the site of many specific transport activities. However, only a few proteins involved in the processes of transport across the chloroplast envelope have been identified already at the molecular level. To discover new envelope transporters, we developed a subcellular proteomic approach, which is aimed to identify the most hydrophobic envelope proteins. This strategy combined the use of highly purified and characterized membrane fractions, extraction of the hydrophobic proteins with organic solvents, SDS/PAGE separation, and tandem mass spectrometry analysis. To process the large amount of MS/MS data, a blast-based program was developed for searching in protein, expressed sequence tag, and genomic plant databases. Among the 54 identified proteins, 27 were new envelope proteins, with most of them bearing multiple α-helical transmembrane regions and being very
article{b77cf787-52f4-485a-b6ae-68b954a67c38, abstract = {Redox chemistry is central to the primary functions of chloroplasts and mitochondria, that is, to energy conversion in photosynthesis and respiration. However, these bioenergetic organelles always contain very small, specialized genetic systems, relics of their bacterial origin. At huge cost, organellar genomes contain, typically, a mere 0.1% of the genetic information in a eukaryotic cell. There is evidence that chloroplast and mitochondrial genomes encode proteins whose function and biogenesis are particularly tightly governed by electron transfer. We have identified nuclear genes for bacterial histidine sensor kinases and aspartate response regulators that seem to be targeted to chloroplast and mitochondrial membranes. Sequence similarities to cyanobacterial redox signalling components indicate homology and suggest conserved sensory and signalling functions. Two-component redox signalling pathways might be ancient, conserved ...
TY - JOUR. T1 - MECHANISM OF ORIENTATION AND LINEAR DICHROISM OF PHOTOSYNTHETIC PARTICLES IN ELECTRIC FIELDS. T2 - CHLOROPLASTS AND CHLOROPHYLL‐PROTEIN COMPLEXES. AU - Gagliano, A. G.. AU - Geacintov, N. E.. AU - Breton, J.. PY - 1986/5. Y1 - 1986/5. N2 - Abstract- The mechanisms of orientation in pulsed and alternating electric fields of thylakoids (derived from the sonication of spinach chloroplasts) and of light‐harvesting chlorophyll a/b‐protein complexes (CPII) were investigated by utilizing linear dichroism techniques. Comparisons of the linear dichroism spectra of thylakoids and CPII particles suggest that the latter are oriented with their directions of largest electronic polarizabilities (and thus probably their largest dimensions) within the thylakoid membrane planes. At low electric field strengths (, 12 V cm−1), and at low frequencies of alternating electric fields (, 0.25 Hz), thylakoid membranes tend to align with their normals parallel to the direction of the applied ...
A typical distribution in which particle volume is related to the total chloroplast volume in a suspension is found in Fig.1. It is apparent that chloroplast volumes in a highly purified preparation vary over a wide range extending from more than 100µm^3 to less than 1µm^3 with a mean near 22.5µm^3. The mean chloroplast volume is similar to volumes calculated from particle dimensions [refs 1-6]: however, the distribution in particle volumes demonstrates size heterogeneity which is difficult to evaluate quantitatively by microscopic examination ...
Electron microscopy shows the chloroplast to consist of an envelope enclosing a complex of membranes, the thylakoid system often joined or stacked into grana; the lipid membranes, contrast with the background when stained with lipophilic electron dense osmium. The space between the envelope and thylakoid membranes is the chloroplast stroma. The envelope is composed of two membranes each about 5.6 nm thick separated by the intra envelope space (10 nm) with areas of high electron density which are possibly contact points between the membranes; they may be involved in transport, i.e., of proteins between cytosol and stroma. The membranes are lipid bilayers, of galactosyl glycerides and phosphatidyl choline, containing carotenoids but no chlorophyll.. The stroma contains indistinct granules and particles, mainly of proteins; the enzyme ribulose bisphosphate carboxylase (Rubisco) is the major soluble protein and may crystallize in unfavorable conditions such as water stress or air pollution. Other ...
Heterologous regulatory elements and flanking sequences have been used in chloroplast transformation of several crop species, but their roles and mechanisms have not yet been investigated. Nucleotide sequence identity in the photosystem II protein D1 (psbA) upstream region is 59% across all taxa; si …
In higher plants, chloroplasts are the site for the photosynthetic reactions, converting solar energy to chemical energy. Within the chloroplast the thylakoid membrane network encloses the soluble lumen compartment. Until recently the knowledge of the lumen composition and function was limited, but a more profound understanding of the thylakoid lumen content is gradually emerging. The discovery that the thylakoid lumen contains numerous enzymes, besides the already known proteins directly involved or associated with the photosynthetic reactions, have changed the view on this compartment.. The first part of the thesis the lumen proteome maps of Arabidopsis and spinach were resolved. These two proteome maps showed good correlation and the same protein groups were represented in the two proteomes. Thirty eight proteins were identified and in combination with an in silico prediction for the proteome it was estimated that at least 80 different proteins are lumen located.. The second part was to ...
Moss chloroplasts should prove useful for studying the cyanobacteria-derived system in chloroplasts. To determine the effects of antibiotics that inhibit bacterial peptidoglycan synthesis, the numbers of chloroplasts in treated Physcomitrella patens cells were counted. Ampicillin and d-cycloserine caused a rapid decrease in the number of chloroplasts per cell. Fosfomycin affected half of the cells, while vancomycin affected a few cells. Conversely, bacitracin had no effect. With the decrease in chloroplast number, macrochloroplasts appeared in antibiotic-treated cells. Removal of the antibiotics resulted in the recovery of chloroplast number, suggesting that the decrease in number was directly dependent on the antibiotic treatment. Microscopic observations showed that the decrease in the number of chloroplasts resulted from cell division without chloroplast division. These results suggest that enzymes derived from the bacterial peptidoglycan synthesis pathway are related to moss chloroplast ...
The data presented here suggest that 3′ end processing may be required for translation of atpB and rbcLmRNAs in Chlamydomonas chloroplasts. Unprocessed atpB transcripts, defined as those that do not accumulate as an abundant size class of approximately 2 kb, were only present in nonpolysomal fractions. Processed mRNAs were present in both polysomal and nonpolysomal fractions. Since the 3′ ends of most chloroplast transcripts are generated from longer pre-mRNAs by exo- and/or endonucleolytic mechanisms (17, 36, 37, 44, 47), this 3′ processing apparatus may interact with or signal the translational machinery.. Our ability to detect a heterogeneous collection of putative processing intermediates or incorrectly processed transcripts for atpBand rbcL suggests that these molecules are relatively stable in the chloroplast. When they were analyzed by RNase protection, it was possible to detect partially processed transcripts in theChlamydomonas chloroplast petD-trnR region (29), and in certain ...
TY - THES. T1 - Utilization of complete chloroplast genomes for phylogenetic studies. AU - Ramlee, Shairul Izan Binti. N1 - WU thesis 6484 Includes bibliographic references. - With summary in English. PY - 2016. Y1 - 2016. N2 - Chloroplast DNA sequence polymorphisms are a primary source of data in many plant phylogenetic studies. The chloroplast genome is relatively conserved in its evolution making it an ideal molecule to retain phylogenetic signals. The chloroplast genome is also largely, but not completely, free from other evolutionary processes such as gene duplication, concerted evolution, pseudogene formation and genome rearrangements. The conservation of the chloroplast genome sequence allows designing primers targeting regions conserved well beyond species boundaries, and amplification of these targets. The small size together with their high copy number in leaf cells greatly facilitates chloroplast genome sequencing. In this thesis, chloroplast phylogenomics was conducted using complete ...
Phototropins are UVA/blue-light receptors involved in controlling the light-dependent physiological responses which serve to optimize the photosynthetic activity of plants and promote growth. The phototropin-induced phosphoinositide (PI) metabolism has been shown to be essential for stomatal opening and phototropism. However, the role of PIs in phototropin-induced chloroplast movements remains poorly understood. The aim of this work is to determine which PI species are involved in the control of chloroplast movements in Arabidopsis and the nature of their involvement. We present the effects of the inactivation of phospholipase C (PLC), PI3-kinase (PI3K) and PI4-kinase (PI4K) on chloroplast relocations in Arabidopsis. The inhibition of the phosphatidylinositol 4,5-bisphospahte [PI(4,5)P2]-PLC pathway, using neomycin and U73122, suppressed the phot2-mediated chloroplast accumulation and avoidance responses, without affecting movement responses controlled by phot1. On the other hand, PI3K and PI4K ...
Photosynthetic development in any plant requires the intracellular co-ordination of chloroplast and nuclear gene expression programs. In this report, we investigate the role of a nuclear gene in photosynthetic development by examining C4 photosynthetic differentiation in a yellow mutant of maize (Zea mays L.). The plastids undifferentiated (pun) mutation disrupts plastid biogenesis in both bundle sheath and mesophyll cells, at an early developmental stage and in a light-independent manner. Chloroplast thylakoids are disrupted in the mutant and both membrane-associated and soluble chloroplast-encoded proteins accumulate at much reduced levels. The observed plastid morphology is consistent with a general defect in chloroplast biogenesis that is most likely exerted at the post-translational level. Despite aberrant chloroplast development, nuclear photosynthetic genes are expressed normally in pun mutants. Thus, neither functional chloroplasts nor the Pun gene product are required to establish nuclear
In leaves and intact chloroplasts, oxidation and reduction have been shown previously to regulate the ATPase activity of thylakoids. Illumination of spinach chloroplast thylakoids in the presence of dithiothreitol, which activates the ability of thylakoids to catalyze sustained ATP hydrolysis in the dark, causes increased incorporation of N-ethylmaleimide into the gamma subunit of coupling factor 1 (CF1). A disulfide bond in the gamma subunit is reduced during activation. The residues involved in this disulfide bond are the same as those in the disulfide linkage reduced during dithiothreitol activation of soluble CF1. The disulfide and dithiol forms of the gamma subunit may be separated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. N-Ethylmaleimide is preferentially incorporated in the dark into the reduced form of the gamma subunit of CF1 in thylakoids previously exposed to dithiothreitol. Only a subpopulation of the CF1 in thylakoids is susceptible to ...
TY - JOUR. T1 - The level of stromal ATP regulates translation of the D1 protein in isolated chloroplasts. AU - Kuroda, Hiroshi. AU - Inagaki, Noritoshi. AU - Satoh, Kimiyuki. PY - 1992/1/1. Y1 - 1992/1/1. N2 - The synthesis of the D1 subunit of the reaction center of photosystem II is light-dependent in isolated chloroplasts. The mechanism of the regulation by light was analyzed using spinach chloroplasts. The light-regulated synthesis of the D1 protein was prevented by the addition of atrazine and the dependence on the concentration of atrazine of the inhibition was practically identical with that of the inhibition of photosynthetic electron transport in photosystem II, as measured by the photoreduction of 2,6-dichlorophenol indophenol. Inhibitors of photosynthetic phosphorylation, such as phloridzin, nigericin and carbonyl cyanide m-chlorophenylhydrazone, also inhibited the light-dependent synthesis of the D1 protein. Determination of the levels of ATP in chloroplasts and the rates of ...
Background At present, plant molecular systematics and DNA barcoding techniques rely heavily on the use of chloroplast gene sequences. Because of the relatively low evolutionary rates of chloroplast genes, there are very few choices suitable for molecular studies on angiosperms at low taxonomic levels, and for DNA barcoding of species. Methodology/Principal Findings We scanned the entire chloroplast genomes of 12 genera to search for highly variable regions. The sequence data of 9 genera were from GenBank and 3 genera were of our own. We identified nearly 5% of the most variable loci from all variable loci in the chloroplast genomes of each genus, and then selected 23 loci that were present in at least three genera. The 23 loci included 4 coding regions, 2 introns, and 17 intergenic spacers. Of the 23 loci, the most variable (in order from highest variability to lowest) were intergenic regions ycf1-a, trnK, rpl32-trnL, and trnH-psbA, followed by trnSUGA-trnGUCC, petA-psbJ, rps16-trnQ, ndhC-trnV, ycf1
TY - JOUR. T1 - Light- and metabolism-related regulation of the chloroplast ATP synthase has distinct mechanisms and functions. AU - Kohzuma, Kaori. AU - Dal Bosco, Cristina. AU - Meurer, Jörg. AU - Kramer, David M.. PY - 2013/5/3. Y1 - 2013/5/3. N2 - The chloroplast CF0-CF1-ATP synthase (ATP synthase) is activated in the light and inactivated in the dark by thioredoxin-mediated redox modulation of a disulfide bridge on its γ subunit. The activity of the ATP synthase is also fine-tuned during steady-state photosynthesis in response to metabolic changes, e.g. altering CO2 levels to adjust the thylakoid proton gradient and thus the regulation of light harvesting and electron transfer. The mechanism of this fine-tuning is unknown. We test here the possibility that it also involves redox modulation. We found that modifying the Arabidopsis thaliana γ subunit by mutating three highly conserved acidic amino acids, D211V, E212L, and E226L, resulted in a mutant, termed mothra, in which ATP synthase ...
In recent years there has been extensive experimental evidence indicating that the nuclear expression of certain genes , in particular those that encode chloroplast proteins is subject to regulation by signals of retrograde plastid origin . This can be done both at the level of transcription and translation of mRNA . Certain plastid origin signals could be identified - these include metabolic precursor of chlorophyll plastochinonu redox state , thioredoxin and glutathione and phosphoenolpyruvate translocator located in the chloroplast inner envelope membrane . Identity plastid other signals , e.g., regulating cell differentiation and morphogenesis leaf remains unexplained . Signaling plastids - nucleus signaling and dependent on the light remain in a fairly complicated relationships , in some cases, are used for different transduction pathways , in others some of the same . Retrograde signaling is likely to be an important part of global regulatory networks that control metabolism and growth of ...
1. Gray, J.C., Genetic manipulation of the chloroplast genome, Biotechnology, 1989, vol. 12, no. 14, pp. 317 335.. 2. Howe, C.J., Barbrook, A.C., Koumandou, V.L., Nisbet, R.E., and Symington, H.A., Evolution of the chloroplast genome, Philos. Trans. R. Soc. Lond., B. Biol. Sci., 2003, vol. 358, no. 1429, pp. 99 107. https://doi.org/10.1098/rstb.2002.1176. 3. Jansen, R.K., Cai, Z.Q., Raubeson, L.A., Daniell, H., Depamphilis, C.W., Leebens-Mack, J., Müller, K.F., Guisinger-Bellian, M., Haberle, R.C., Hansen, A.K., Chumley, T.W., Lee, S.B., Peery, R., McNeal, J.R., Kuehl, J.V., and Boore, J.L., Analysis of 81 genes from 64 plastid genomes resolves relationships in angiosperms and identifies genome-scale evolutionary patterns, Proc. Natl. Acad. Sci. U. S. A., 2007, vol. 104, no. 49, pp. 19369 19374. https://doi.org/10.1073/pnas.0709121104. 4. Odintsova, M.S. and Yurina, N.P., Chloroplast genomics of land plants and algae, Biotechnol. Appl. Photosyn. Protein: Biochips, Biosensors, Biodevices, 2006, ...
CONIFER CHLOROPLAST GENOMES (NEARLY) SEQUENCED ????? To date a number of chloroplast genomes have been sequenced. A few years ago there were plans to sequence the entire chloroplast genome from a conifer. Has anybody got any news about what has been done to date in this regard? Id appreciate any information. peter sibbald at EMBL-Heidelberg.DE ...
A 2.4 kb region of theEuglena gracilis chloroplast genome containing the genespsbT, psbH andpsbN was characterized. The mRNAs transcribed frompsbB, psbT, p
1. Stern, D. B., Goldschmidt-Clermont, M., and Hanson, M. R. (2010) Chloroplast RNA metabolism. Annual Rev Plant Biol 61, 125-155.. 2. Reed, M. L., and Hanson, M. R. (1997) A heterologous maize rpoB editing site is recognized by transgenic tobacco chloroplasts. Mol Cell Biol 17, 6948-6952.. 3. Reed, M. L., Lyi, S. M., and Hanson, M. R. (2001) Edited transcripts compete with unedited mRNAs for trans-acting editing factors in higher plant chloroplasts. Gene 272, 165-171.. 4. Reed, M. L., Peeters, N. M., and Hanson, M. R. (2001) A single alteration 20 nt 5 to an editing target inhibits chloroplast RNA editing in vivo. Nucleic Acids Res 29, 1507-1513.. 5. Hegeman, C. E., Hayes, M. L., and Hanson, M. R. (2005) Substrate and cofactor requirements for RNA editing of chloroplast transcripts in Arabidopsis in vitro. Plant Journal 42, 124-132.. 6. Heller, W. P., Hayes, M. L., and Hanson, M. R. (2008) Cross-competition in editing of chloroplast RNA transcripts in vitro implicates sharing of trans-factors ...
Physical and gene map of the green alga Nephroselmis chloroplast genome, showing the typical structural arrangement found in land plants. Genes located on the inside of the map are transcribed counterclockwise, and genes on the outside are transcribed clockwise. The inner circle shows where the Small Single-Copy region (SSC), Large Single Copy region (LSC) and Inverted Repeats (IR), are located. The thick lines on the actual map are the IRs. Figure from Turmel et al. (1999). © 1999 National Academy of Sciences, U.S.A. The B copy (IR-B) of the inverted repeat is the copy that is missing in legume taxa in the IRLC.. ...
TY - JOUR. T1 - Faithful editing of a tomato-specific mRNA editing site in transgenic tobacco chloroplasts. AU - Karcher, D.. AU - Kahlau, Sabine. AU - Bock, R.. PY - 2008. Y1 - 2008. N2 - RNA editing sites and their site-specific trans-acting recognition factors are thought to have coevolved. Hence, evolutionary loss of an editing site by a genomic mutation is normally followed by the loss of the specific recognition factor for this site, due to the absence of selective pressure for its maintenance. Here, we have tested this scenario for the only tomato-specific plastid RNA editing site. A single C-to-U editing site in the tomato rps12 gene is absent from the tobacco and nightshade plastid genomes, where the presence of a genomic T nucleotide obviates the need for editing of the rps12 mRNA. We have introduced the tomato editing site into the tobacco rps12 gene by plastid transformation and find that, surprisingly, this heterologous site is efficiently edited in the transplastomic plants. This ...
Species of Bryopsidales form ecologically important components of seaweed communities worldwide. These siphonous macroalgae are composed of a single giant tubular cell containing millions of nuclei and chloroplasts, and harbor diverse bacterial communities. Little is known about the diversity of chloroplast genomes (cpDNAs) in this group, and about the possible consequences of intracellular bacteria on…
Ferredoxin-NADP+-oxidoreductase (FNR) is a FAD-containg enzyme found both in the chloroplasts and non-photosynthetic plastids of higher plants. In chloroplasts, FNR has a well-defined role in linear electron flow, and in the root plastids, FNR is needed for nitrogen metabolism. In Arabidopsis thaliana, FNR is encoded by a gene family: At1g30510 and At4g05390 encode the root isozyme of FNR and At5g66190 and At1g20020 encode the leaf/chloroplast isozyme, which share a high degree of homology. Since FNR is a crucial determinant for the acclimation of the photosynthetic machinery, we have recently focused on resolving the specific physiological roles of the two distinct chloroplast-targeted FNR isoforms using the Arabidopsis fnr knock-out mutants (Lintala et al. 2007; 2009; 2012). We have also resolved the binding partner and the physiological significance of FNR shuttling within the chloroplast (Benz et al. 2009; 2010; Lintala et al.2014), and established differential drought stress -induced ...
Plastid-to-nucleus retrograde signaling coordinates nuclear gene expression with chloroplast function and is essential for the photoautotrophic life-style of plants. Three retrograde signals have been described, but little is known of their signaling pathways. We show here that GUN1, a chloroplast-localized pentatricopeptide-repeat protein, and ABI4, an Apetala 2 (AP2)-type transcription factor, are common to all three pathways. ABI4 binds the promoter of a retrograde-regulated gene through a conserved motif found in close proximity to a light-regulatory element. We propose a model in which multiple indicators of aberrant plastid function in Arabidopsis are integrated upstream of GUN1 within plastids, which leads to ABI4-mediated repression of nuclear-encoded genes. |P /|
What is a plastid Cell | Process of Photosynthesis | Chloroplasts, chromoplast, leucoplasts & Other Plastids. Learn more about [email protected]
Kelly, A. A.; Kalisch, B.; Hoelzl, G.; Schulze, S.; Thiele, J.; Melzer, M.; Roston, R. L.; Benning, C.; Doermann, P.: Synthesis and transfer of galactolipids in the chloroplast envelope membranes of Arabidopsis thaliana. Proceedings of the National Academy of Sciences of the United States of America 113 (38), S. 10714 - 10719 (2016 ...
Biology. Physical Sciences. Science and Industry. M.Sc. Bio Technology: Chloroplast Engineering in Orissa. M.Sc. Bio Technology: Chloroplast Engineering. The University at Jyoti Vihar provides Post-Graduate education in Twenty-seven subjects through Twenty Post-Graduate Departments. The University Post-Graduate Departments offer one-year study Programme
Substitutions occurring in noncoding sequences of the plant chloroplast genome violate the independence of sites that is assumed by substitution models in molecular evolution. The probability that a substitution at a site is a transversion, as opposed to a transition, increases significantly with in …
Studte, Carsten (2012): Characterization of the membrane protein Prat1 in the inner envelope of chloroplasts. Dissertation, LMU München: Faculty of Biology ...
Houben, E., Nilsson, R., de Gier, J.W., Brunner, J., Hoffman, N.E. and van Wijk, K.J. (1999) Reconstitution of co-translational targeting of polytopic membrane proteins to the thylakoids in a homologous chloroplast translation system. In: NATO advanced research workshop. The Chloroplast; From Molecular Biology to Biotechnology. (Dr. J. Argyroudi-Akoyunoglou and H. Senger, eds.), 327- ...
FtsH is an evolutionary conserved membrane-bound metalloprotease complex. While in most prokaryotes FtsH is encoded by a single gene, multiple FtsH genes are found in eukaryotes. Genetic and biochemical data suggest that the Arabidopsis chloroplast FtsH is a hetero-hexamer. This raises the question why photosynthetic organisms require a heteromeric complex, whereas in most bacteria a homomeric one is sufficient. To gain structural information of the possible complexes, the Arabidopsis FtsH2 (type B) and FtsH5 (type A) were modeled. An in silico study with mixed models of FtsH2/5 suggests that heteromeric hexamer structure with ratio of 4∶2 is more likely to exists. Specifically, calculation of the buried surface area at the interfaces between neighboring subunits revealed that a hetero-complex should be thermodynamically more stable than a homo-hexamer, due to the presence of additional hydrophobic and hydrophilic interactions. To biochemically assess this model, we generated Arabidopsis transgenic
Unknown protein; FUNCTIONS IN: molecular_function unknown; INVOLVED IN: biological_process unknown; LOCATED IN: chloroplast thylakoid membrane, chloroplast thylakoid lumen, chloroplast; EXPRESSED IN: 22 plant structures; EXPRESSED DURING: 13 growth /.../; Has 38 Blast hits to 38 proteins in 13 species: Archae - 0; Bacteria - 0; Metazoa - 0; Fungi - 0; Plants - 38; Viruses - 0; Other Eukaryotes - 0 (source: NCBI BLink ...
Figure 1: Model of dual function of the pyruvate dehydrogenase complex. In this project, we aim at elucidating the precise molecular working mode of this regulatory principle involving metabolic control of gene expression. By following molecular, genetical, and biochemical approaches in C. reinhardtii, we use in vivo and in vitro techniques to characterize both the RNA binding and the enzymatic forms of DLA2 which appears to shuttle between different protein sub-complexes. A special focus is on the dynamics and composition of these complexes and the role of acetate/acetyl-CoA for balancing both functions of DLA2. This work is complemented by related analyses in cyanobacteria and higher plants, to test for an evolutionary conservation of such a regulatory switch.. A second project is based on recent work from our group that has shown that in C. reinhardtii the translation of the psbD mRNA encoding the D2 protein of PSII is redox-regulated via a single disulphide bridge between the trans-acting ...
Escherichia coli minicells harbouring the cloned restriction fragment Sall S9 from P. hybrida chloroplast DNA synthesize the beta and epsilon polypeptide subuni
TY - JOUR. T1 - Nucleotide sequence of the chloroplast 16S rRNA gene from pea (Pisum sativum L.). AU - Cerutti, H.. AU - Jagendorf, A. T.. PY - 1991/7/1. Y1 - 1991/7/1. UR - http://www.scopus.com/inward/record.url?scp=0026196725&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=0026196725&partnerID=8YFLogxK. U2 - 10.1007/BF00036812. DO - 10.1007/BF00036812. M3 - Article. C2 - 1868211. AN - SCOPUS:0026196725. VL - 17. SP - 125. EP - 126. JO - Plant Molecular Biology. JF - Plant Molecular Biology. SN - 0167-4412. IS - 1. ER - ...
Molecular phyl葉緑体rbcL遺伝子に基づく蘚類ギボウシゴケ目の分子系統学的研究ogeny of the Grimmiales (Musci) based on chloroplast rbcL sequences, Hikobia, 14巻, 1号, pp.55-pp. ...
The subspecies of Physaria kingii (S. Watson) OKane and Al-Shehbaz (Brassicaceae) have historically been a difficult group to delimit taxonomically based on morphology, geography, and ecology. The taxa have been moved between genera as well among varieties, subspecies, and full species many times over. This study addressed the systematics relationships of the subspecies of P. kingii using a combination of molecular (both nuclear and chloroplast DNA sequences), morphological, geographical, and ecological data. Three non-coding DNA regions were chosen: the internal transcribed spacer (ITS) region of nuclear ribosomal DNA and the chloroplast rps intron and the chloroplast ndhC-trnV intergenic spacer. Eighty-seven aligned sequences in total were selected and networks were constructed using SplitsTree for exploratory data analyses to identify any genealogical discordance for each of the regions in addition to a combined chloroplast region. With the prior knowledge of possible hybridization among P. k. subsp
Postglacial migration is a major factor responsible for the patterns of genetic variation we see in natural populations. Fossil pollen data indicate that early postglacial colonists such as oak, were able to take both western and eastern migration routes into Britain. Analysis at a finer level is now permitted by the use of modern molecular techniques. A 13-bp duplication in the chloroplast tRNALeul intron occurs in natural populations of East Anglian oaks, but is not found in other parts of Britain or from mainland Europe. The distribution of this marker suggests that the mutation occurred either in southern England, or during migration from the mainland, and became fixed in a source population from which East Anglia was colonized. Planting of non-native trees for roadside boundaries and in the grounds of old houses and estates, explains the absence of the marker from some East Anglian oaks.. ...
Plants need sunlight to feed and grow. Without light, the photosynthesis, the reaction by which the plant chloroplasts convert atmospheric CO2 and water into sugars and oxygen, cannot take place.
if you inject a chloroplast into an animal cell it will go through autophagocytosis because the cell iterprets it like foreign. in order for a chloroplast to function it must be in a plant cell because some genes, during evolution some genes were transfered between the chloroplast genome and the nucleus. However that would not happen as the cell would probably treat a foreign chloroplast or a foreign nucleus as foreign and digest it. Another possibility is for the cell to undergo apoptosis. Unfortunaly, i dont enough biology to answer such a complex question. Sorry ...
In this study we report the development of primers to amplify polymorphic chloroplast simple sequence repeats in the genus Hordeum, which includes cultivated barley (H. vulgare ssp. vulgare) and its wild progenitor H. vulgare ssp. spontaneum. Polymorphic products were amplified in a wide range of Hordeum spp. and intraspecific variation was detected in both cultivated and wild barley. A decrease in cytoplasmic diversity was observed between sspp. spontaneum and vulgare as well as between ssp. vulgare landraces and cultivars, which is characteristic of domestication processes in many crop species. We also observed possible evidence for reticulate evolution of H. brachyantherum polyploids, with apparent multiple cytoplasmic introgressions during successive polyploidization events. ...