title: Dynamics of post-translational modifications and protein stability in the stroma of Chlamydomonas reinhardtii chloroplasts.
abstract: The proteome of any system is a dynamic entity dependent on the intracellular concentration of the entire set of expressed proteins. In turn, this whole protein concentration will be reliant on the stability/turnover of each protein as dictated by their relative rates of synthesis and degradation. In this study, we have investigated the dynamics of the stromal proteome in the model organism Chlamydomonas reinhardtii by characterizing the half-life of the whole set of proteins. 2-DE stromal proteins profiling was set up and coupled with MS analyses. These identifications featuring an average of 26% sequence coverage and eight non-redundant peptides per protein have been obtained for 600 independent samples related to 253 distinct spots. An interactive map of the global stromal proteome, of 274 distinct protein variants is now available on-line at http://www.isv.cnrs-gif.fr/gel2dv2/. N-α-terminal-Acetylation (NTA) was noticed to be the most frequently detectable post-translational modification, and new experimental data related to the chloroplastic transit peptide cleavage site was obtained. Using this data set supplemented with series of pulse-chase experiments, elements directing the relationship between half-life and N-termini were analyzed. Positive correlation between NTA and protein half-life suggests that NTA could contribute to protein stabilization in the stroma.
authors.affiliation: CNRS, ISV, UPR2355, Gif-sur-Yvette, France.
authors.forename: Willy V
authors.initials: WV
authors.lastname: Bienvenut
authors.forename: Christelle
authors.initials: C
authors.lastname: Espagne
authors.forename: Aude
authors.initials: A
authors.lastname: Martinez
authors.forename: Wojetec
authors.initials: W
authors.lastname: Majeran
authors.forename: Benoît
authors.initials: B
authors.lastname: Valot
authors.forename: Michel
authors.initials: M
authors.lastname: Zivy
authors.forename: Olivier
authors.initials: O
authors.lastname: Vallon
authors.forename: Zach
authors.initials: Z
authors.lastname: Adam
authors.forename: Thierry
authors.initials: T
authors.lastname: Meinnel
authors.forename: Carmela
authors.initials: C
authors.lastname: Giglione
mesh_terms: D000595:Amino Acid Sequence; D016825:Chlamydomonas reinhardtii / Q000378:metabolism*; D002736:Chloroplasts / Q000378:metabolism*; D002853:Chromatography, Liquid; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D007700:Kinetics; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000032:analysis* / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D055550:Protein Stability; D020543:Proteome / Q000032:analysis / Q000378:metabolism; D040901:Proteomics / Q000379:methods; D017386:Sequence Homology, Amino Acid; D013997:Time Factors
chemical_list: D010940:Plant Proteins; D020543:Proteome