title: Protein-protein and protein-function relationships in Arabidopsis photosystem I: cluster analysis of PSI polypeptide levels and photosynthetic parameters in PSI mutants.
abstract: In flowering plants, photosystem I (PSI) mediates electron transport across the thylakoid membrane and contains at least 14 proteins. The availability of co-suppression and/or mutant lines deficient for individual PSI polypeptides in Arabidopsis thaliana allows one to assign functions to PSI subunits. We have performed cluster analysis on an extensive set of data on PSI polypeptide levels in ten different PSI mutants. This type of analysis serves to group proteins that exhibit similar changes in amount in different genotypes, and also identifies genotypes which show similar PSI compositions. The interdependence of levels of PSI-C, -D and -E, of -H and -L, and of Lhca2 and 3, which was previously proposed based on the study of single genotypes or on cross-linking experiments, was confirmed by our analyses. In addition, the levels of the lumenal subunits F and N are found to be interdependent. The incorporation of photosynthetic parameters into the cluster analysis revealed that the level of photosynthetic state transitions correlates with the abundance of PSI-H in all 8 genotypes tested, supporting the hypothesis that PSI-H serves as a docking site for LHCII during state transitions.
authors.affiliation: Zentrum zur Identifikation von Genfunktionen durch Insertionsmutagenese bei Arabidopsis thaliana (ZIGIA), Max-Planck-Institut für Zuchtungsforschung, Carl-von-Linné Weg 10, 50829 Köln, Germany.
authors.forename: Paolo
authors.initials: P
authors.lastname: Pesaresi
authors.forename: Claudio
authors.initials: C
authors.lastname: Varotto
authors.forename: Erik
authors.initials: E
authors.lastname: Richly
authors.forename: Angela
authors.initials: A
authors.lastname: Lessnick
authors.forename: Francesco
authors.initials: F
authors.lastname: Salamini
authors.forename: Dario
authors.initials: D
authors.lastname: Leister
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D017343:Genes, Plant; D046911:Macromolecular Substances; D008958:Models, Molecular; D009154:Mutation; D010788:Photosynthesis / Q000235:genetics; D045322:Photosynthetic Reaction Center Complex Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D045331:Photosystem I Protein Complex; D021122:Protein Subunits
chemical_list: D029681:Arabidopsis Proteins; D046911:Macromolecular Substances; D045322:Photosynthetic Reaction Center Complex Proteins; D045331:Photosystem I Protein Complex; D021122:Protein Subunits