ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Characterization of Chloroplast Clp proteins in Arabidopsis: Localization, tissue specificity and stress responses (2002)
    Oxford, UK : Munksgaard International Publishers
    Physiologia plantarum 114 (2002), S. 0 
    Details
    ISSN: 1399-3054
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: The ATP-dependent Clp protease is one of the newly identified proteolytic systems in plant organelles that incorporate the activity of molecular chaperones to target specific polypeptide substrates and avoid inadvertent degradation of others. We describe new nuclear-encoded ClpC (ClpC1) and ClpP (ClpP3–5) isomers in Arabidopsis thaliana that raise the total number of identified Clp proteins to 19. The extra Clp proteins are localized within the stroma of chloroplasts along with the ClpD, –P1 and –P6 proteins. Potential differential regulation among these Clp proteins was analysed at both the mRNA and protein level. A comparison between different tissues showed increasing amounts of all plastid Clp proteins from roots to stems to leaves suggested the greatest abundance of proteins was in chloroplasts. The increases in protein were mirrored at the mRNA level for most ClpP isomers (ClpP1, −3, −4 and −6) but not for the three Hsp100 proteins (ClpC1, –C2 and –D) and ClpP5, which exhibited little change in transcript levels, suggesting post-transcriptional/translational regulation. Potential stress induction was also tested for all chloroplast Clp proteins by a series of brief and prolonged stress conditions. Short-term moderate and severe stresses (desiccation, high salt, cold, heat, oxidation, wounding and high light) all failed to elicit significant or rapid increases in any chloroplast Clp protein. However, increases in mRNA and protein content for ClpD and several ClpP isomers did occur during long-term high light and cold acclimation of Arabidopsis plants. These results reveal the great complexity of Clp proteins within the stroma of plant chloroplasts, and that these proteins, rather than being rapidly induced stress proteins, are primarily constitutive proteins that may also be involved in plant acclimation to different physiological conditions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1034/j.1399-3054.2002.1140113.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    FtsH proteases in chloroplasts and cyanobacteria (2005)
    Oxford, UK; Malden, USA : Munksgaard International Publishers
    Physiologia plantarum 123 (2005), S. 0 
    Details
    ISSN: 1399-3054
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: FtsH is a membrane-bound ATP-dependent metalloprotease complex found in prokaryotes and organelles of eukaryotic cells. It consists of one or two trans-membrane helices at its amino-terminus, a highly conserved ATPase domain, which relates it to the AAA protein family, and a zinc-binding domain towards its carboxy-terminus that serves as the proteolytic site. Most bacteria contain a single FtsH gene, but the cyanobacterium Synechocystis has four. The Arabidopsis thaliana genome contains 12 genes encoding FtsH proteins, nine of them can be targeted to chloroplasts, whereas the other three are mitochondrial. Chloroplast FtsH protease is located in the thylakoid membrane, where it forms complexes, most likely hexamers, whose ATPase and proteolytic domains are exposed to the stroma. It is involved in the degradation of the D1 protein of photosystem II reaction centre during its repair from photoinhibition, as well as in the degradation of unassembled proteins in the thylakoid and the stroma. In Arabidopsis, FtsH2 is the most abundant isomer, followed by FtsH5, 8 and 1. This hierarchy is well reflected in the severity of the variegated phenotype of mutants in these genes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1399-3054.2004.00436.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Correlative changes in sucrose uptake, ATPase activity and membrane fluidity in carnation petals during senescence (1983)
    Oxford, UK : Blackwell Publishing Ltd
    Physiologia plantarum 58 (1983), S. 0 
    Details
    ISSN: 1399-3054
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Apparent sucrose uptake. ATPase activity and membrane fluidity changes were studied during the development and senescence of carnation flowers (Dianthus caryophyllus L., cv. Cerise Royallette). Typical changes associated with senescence of a cut flower, such as respiration, ethylene production and fresh weight, were measured. Concomitant with a rise in respiration and ethylene production and a decline in fresh weight, a sharp decrease in apparent sucrose uptake was observed. Sucrose uptake was pH dependent (pH optimum, 5.5) and influenced by membrane integrity. Apparently, the activity of ATPase is related to sucrose uptake, because similar changes occurred during flower development. In addition, the activity of ATPase was well correlated with membrane fluidity.It is suggested that sucrose uptake is controlled by ATPase activity, which in turn is modulated by membrane lipid fluidity. The decline in membrane fluidity associated with senescence leads to a corresponding reduction in ATPase activity and sucrose uptake. Further evidence supporting this view comes from experiments in which senescence was enhanced by 1-aminocyclopropane-l-carboxylic acid. It shortened the time to decline in fresh weight, rise in respiration and ethylene production. In parallel, reduction in membrane fluidity, ATPase activity and sucrose uptake were observed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1399-3054.1983.tb04178.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    A mutation in the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase that reduces the rate of its incorporation into holoenzyme (1995)
    Springer
    Photosynthesis research 43 (1995), S. 143-147 
    Details
    ISSN: 1573-5079
    Keywords: assembly ; Rubisco ; stability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A mutant of the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), in which Arg53 is replaced by Glu, was synthesized and imported into isolated chloroplasts. The mutant protein was efficiently imported into the chloroplast and correctly processed to the mature size. Like the wild type protein, it was stable over a period of at least 2 h. Unlike the wilk-type protein however, most of the mutant protein was not assembled with holo-Rubisco at the end of a 10-min import reaction. It migrated instead as a diffused band on a non-denaturing gel, slower than the precursor protein, but faster than the holoenzyme. The level of the unassembled mutant protein in the stroma decreased with time, while its level in the assembled fraction has increased, indicating that this protein is a slowly-assembled, rather than a non-assembled, mutant of the small suubunit of Rubisco. Accumulation of the mutant protein in the holoenzyme fraction was dependent on ATP and light. The transient species, migrating faster than the holoenzyme but slower than the precursor protein, may represent an intermediate in the assembly process of the small subunit of Rubisco
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00042971
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Mutations in the processing site of the precursor of ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit: effects on import, processing, assembly and stability (1995)
    Springer
    Plant molecular biology 29 (1995), S. 53-61 
    Details
    ISSN: 1573-5028
    Keywords: chloroplast ; Pisum sativum ; precursor ; processing ; Rubisco
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The small subunit (SSU) of Rubisco is synthesized in the cytosol in a precursor form. Upon import into the chloroplast, it is proteolytically processed at a Cys-Met bond to yield the mature form of the protein. To assess the importance of the Met residue for recognition and processing by the stromal peptidase, we substituted this residue with either Thr, Arg or Asp. The mutant precursor proteins were imported into isolated chloroplasts, and the products of the import reactions were analyzed. Mutants containing Thr or Arg residues at the putative processing site were processed to a single peptide, comigrating with the wild-type protein. N-terminal radio-sequencing revealed that these mutants were processed at the Cys-Thr and the Cys-Arg bond, respectively. After import of the Asp-containing mutant, four processed forms of the protein were observed. Analysis of the most abundant one, co-migrating with the wild-type protein, demonstrated that this species was also a product of correct processing, at the Cys-Asp bond. All the correctly processed peptides were found to be associated with the holoenzyme of Rubisco, and remained stable within the chloroplast, like the wild-type protein. The results of this study, together with previous ones, suggest that proper recognition and processing of the SSU precursor are more affected by residues N-terminal to the processing site than by the residue on the C-terminal side of this site.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00019118
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Protein stability and degradation in chloroplasts (1996)
    Springer
    Plant molecular biology 32 (1996), S. 773-783 
    Details
    ISSN: 1573-5028
    Keywords: chloroplast ; peptidase ; protease ; protein stability ; proteolysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00020476
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Degradation of mistargeted OEE33 in the chloroplast stroma (1996)
    Springer
    Plant molecular biology 30 (1996), S. 925-933 
    Details
    ISSN: 1573-5028
    Keywords: Chloroplast ; Clp protease ; oxygen-evolving complex ; proteolysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract OEE33, a component of the oxygen-evolving enzyme in chloroplasts, normally resides in the thylakoid lumen. In an attempt to study the fate of mistargeted proteins in chloroplasts, we substituted the bipartite transit peptide of OEE33 with that of CAB7, an integral thylakoid-membrane protein. As a result, when imported into isolated chloroplasts, the chimeric protein was targeted to the stroma instead of the thylakoid lumen. Whereas the wild-type OEE33 was totally stable for at least 2 h, the chimeric protein was rapidly degraded, with a half-life of 60 min. Degradation of the chimeric protein was stimulated by ATP supplementation. Degradation could also be observed in lysed chloroplasts, in an ATP-stimulated manner. When lysates were fractionated, the proteolytic activity was found to be associated mainly with the stromal fraction. This activity was very effectively inhibited by all tested inhibitors of serine proteases. Western blot analysis demonstrated that the stromal fraction active in degrading the chimeric OEE33 contains ClpC and ClpP, homologues of the regulatory and proteolytic subunits, respectively, of the bacterial, ATP-dependent, serine-type Clp protease.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00020804
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Effects of light and temperature on expression of ClpC, the regulatory subunit of chloroplastic Clp protease, in pea seedlings (1996)
    Springer
    Plant molecular biology 31 (1996), S. 673-676 
    Details
    ISSN: 1573-5028
    Keywords: Chloroplast ; Clp protease ; Pisum sativum ; proteolysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Chloroplasts contain homologues to the proteolytic and regulatory subunits of bacterial ATP-dependent Clp protease. We tested the effects of light and temperature on the expression of ClpC, the chloroplastic homologue of the regulatory subunit. ClpC mRNA was present in all tissues of pea seedlings, most abundantly in leaves. Higher levels of the message were found in green leaves than in etiolated ones. Exposure of etiolated seedlings to light resulted in further accumulation of the transcript. Similarly, ClpC protein level was lower in etiolated leaves, and increased upon exposure to light. Transferring seedlings from 25°C to either 17 or 37°C resulted in a decrease in both ClpC mRNA and protein, with the lower temperature being the most effective.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00042238
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    facet.materialart.
    Unknown
    The crystal structure of Deg9 reveals a novel octameric-type HtrA protease (2017)
    Springer Nature
    Details
    Publication Date: 2017-11-27
    Print ISSN: 2055-026X
    Electronic ISSN: 2055-0278
    Topics: Biology
    Published by Springer Nature
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 10
    facet.materialart.
    Unknown
    Cutting edge of chloroplast proteolysis (2002)
    Cell Press
    Details
    Publication Date: 2002-10-01
    Print ISSN: 1360-1385
    Electronic ISSN: 1878-4372
    Topics: Biology , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Published by Cell Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...