Affiliation:
1. Department of Plant Biology, Carnegie Institution of Washington, 260 Panama Street, Stanford, California 94305 (P.A., D.A.C.S., M.L.P., D.H.P., N.E.H.)
2. Departement d'Ecophysiologie Vegetale et de Microbiologie Commissariat à l'Energie Atomique/Cadarache, F–13108 St. Paul lez Durance cedex, France (L.N.)
Abstract
Abstract
The chloroplast signal recognition particle (cpSRP) is a protein complex consisting of 54- and 43-kD subunits encoded by the fifty-four chloroplast, which encodes cpSRP54 (ffc), and chaos (cao) loci, respectively. Two new null alleles in the ffc locus have been identified.ffc1-1 is caused by a stop codon in exon 10, whileffc1-2 has a large DNA insertion in intron 8.ffc mutants have yellow first true leaves that subsequently become green. The reaction center proteins D1, D2, and psaA/B, as well as seven different light-harvesting chlorophyll proteins (LHCPs), were found at reduced levels in the youngffc leaves but at wild-type levels in the older leaves. The abundance of the two types of LHCP was unaffected by the mutation, while two others were increased in the absence of cpSRP54. Null mutants in the cao locus contain reduced levels of the same subset of LHCP proteins as ffc mutants, but are distinguishable in four ways: young leaves are greener, the chlorophylla/b ratio is elevated, levels of reaction center proteins are normal, and there is no recovery in the level of LHCPs in the adult plant. The data suggest that cpSRP54 and cpSRP43 have some nonoverlapping roles and that alternative transport pathways can compensate for the absence of a functional cpSRP.
Publisher
Oxford University Press (OUP)
Subject
Plant Science,Genetics,Physiology
Cited by
97 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献