title: Expression of the nuclear encoded OEE1 protein is required for oxygen evolution and stability of photosystem II particles in Chlamydomonas reinhardtii.
abstract: In Chlamydomonas reinhardtii the oxygen evolving enhancer protein 1 (OEE1), which is part of the oxygen evolving complex of photosystem II (PS II), is coded for by a single nuclear gene (psb1). The nuclear mutant FuD44 specifically lacks the OEE1 polypeptide and is completely deficient in photosynthetic oxygen evolution. In this mutant a 5 kb DNA insertion into the 5' region of the psb1 gene results in the complete absence of OEE1 mRNA and protein. A revertant, FuD44-R 2, which is capable of 30% of the photosynthetic oxygen evolution of wild-type cells, has lost 4 kb of the 5 kb DNA insert, and accumulates both OEE1 mRNA and protein, although at levels somewhat less than those of wild-type cells. Absence of the OEE1 protein in the FuD44 mutant does not affect the accumulation of other nuclear encoded PS II peripheral polypeptides. OEE1 absence does, however, result in a more rapid turnover of the chloroplast encoded PS II core polypeptides, thus resulting in a substantial deficiency of PS II core polypeptides in FuD44 cells. These PS II core proteins again accumulate in revertant FuD44-R2 cells.
mesh_terms: D020418:Algal Proteins; D002467:Cell Nucleus / Q000378:metabolism; D002696:Chlamydomonas / Q000235:genetics* / Q000378:metabolism; D002734:Chlorophyll / Q000235:genetics*; D005796:Genes; D045342:Light-Harvesting Protein Complexes; D009154:Mutation; D010100:Oxygen / Q000378:metabolism*; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D010940:Plant Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D014158:Transcription, Genetic
chemical_list: D020418:Algal Proteins; D045342:Light-Harvesting Protein Complexes; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D010940:Plant Proteins; D012333:RNA, Messenger; C052389:oxygen-evolving enhancer protein 1, plant; D002734:Chlorophyll; D010100:Oxygen