Cryo-EM study of the spinach chloroplast ribosome reveals the structural and functional roles of plastid-specific ribosomal proteins.

ABSTRACT: Protein synthesis in the chloroplast is carried out by chloroplast ribosomes (chloro-ribosome) and regulated in a light-dependent manner. Chloroplast or plastid ribosomal proteins (PRPs) generally are larger than their bacterial counterparts, and chloro-ribosomes contain additional plastid-specific ribosomal proteins (PSRPs); however, it is unclear to what extent these proteins play structural or regulatory roles during translation. We have obtained a three-dimensional cryo-EM map of the spinach 70S chloro-ribosome, revealing the overall structural organization to be similar to bacterial ribosomes. Fitting of the conserved portions of the x-ray crystallographic structure of the bacterial 70S ribosome into our cryo-EM map of the chloro-ribosome reveals the positions of PRP extensions and th

SUBMITTER: Sharma MR 

PROVIDER: S-EPMC2148287 | biostudies-literature | 2007 Dec

REPOSITORIES: biostudies-literature