title: Proteomic analysis of a model unicellular green alga, Chlamydomonas reinhardtii, during short-term exposure to irradiance stress reveals significant down regulation of several heat-shock proteins.
abstract: Oxygenic photosynthetic organisms often suffer from excessive irradiance, which cause harmful effects to the chloroplast proteins and lipids. Photoprotection and the photosystem II repair processes are the mechanisms that plants deploy to counteract the drastic effects from irradiance stress. Although the protective and repair mechanisms seemed to be similar in most plants, many species do confer different level of tolerance toward high light. Such diversity may originate from differences at the molecular level, i.e., perception of the light stress, signal transduction and expression of stress responsive genes. Comprehensive analysis of overall changes in the total pool of proteins in an organism can be performed using a proteomic approach. In this study, we employed 2-DE/LC-MS/MS-based comparative proteomic approach to analyze total proteins of the light sensitive model unicellular green alga Chlamydomonas reinhardtii in response to excessive irradiance. Results showed that among all the differentially expressed proteins, several heat-shock proteins and molecular chaperones were surprisingly down-regulated after 3-6 h of high light exposure. Discussions were made on the possible involvement of such down regulation and the light sensitive nature of this model alga.
authors.affiliation: Department of Biochemistry and Center for Excellence in Protein Structure and Function, Mahidol University, Bangkok 10400, Thailand.
authors.forename: Bancha
authors.initials: B
authors.lastname: Mahong
authors.forename: Suttiruk
authors.initials: S
authors.lastname: Roytrakul
authors.forename: Narumon
authors.initials: N
authors.lastname: Phaonaklop
authors.forename: Janewit
authors.initials: J
authors.lastname: Wongratana
authors.forename: Kittisak
authors.initials: K
authors.lastname: Yokthongwattana
mesh_terms: D016825:Chlamydomonas reinhardtii / Q000378:metabolism* / Q000528:radiation effects*; D015180:Electrophoresis, Gel, Two-Dimensional; D006360:Heat-Shock Proteins / Q000378:metabolism*; D008027:Light; D010940:Plant Proteins / Q000378:metabolism*; D040901:Proteomics / Q000379:methods*; D015398:Signal Transduction / Q000528:radiation effects; D053719:Tandem Mass Spectrometry
chemical_list: D006360:Heat-Shock Proteins; D010940:Plant Proteins