title: Translation factors direct intrinsic ribosome dynamics during translation termination and ribosome recycling.
abstract: Characterizing the structural dynamics of the translating ribosome remains a major goal in the study of protein synthesis. Deacylation of peptidyl-tRNA during translation elongation triggers fluctuations of the pretranslocation ribosomal complex between two global conformational states. Elongation factor G-mediated control of the resulting dynamic conformational equilibrium helps to coordinate ribosome and tRNA movements during elongation and is thus a crucial mechanistic feature of translation. Beyond elongation, deacylation of peptidyl-tRNA also occurs during translation termination, and this deacylated tRNA persists during ribosome recycling. Here we report that specific regulation of the analogous conformational equilibrium by translation release and ribosome recycling factors has a critical role in the termination and recycling mechanisms. Our results support the view that specific regulation of the global state of the ribosome is a fundamental characteristic of all translation factors and a unifying theme throughout protein synthesis.
authors: Department of Chemistry, Columbia University, New York, New York, USA.
authors: Samuel H
authors: SH
authors: Sternberg
authors: Jingyi
authors: J
authors: Fei
authors: Noam
authors: N
authors: Prywes
authors: Kelly A
authors: KA
authors: McGrath
authors: Ruben L
authors: RL
authors: Gonzalez
mesh_terms: D002232:Carbocyanines / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D005453:Fluorescence; D007700:Kinetics; D008954:Models, Biological; D010443:Peptide Chain Termination, Translational; D010454:Peptide Termination Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012269:Ribosomal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012270:Ribosomes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D002232:Carbocyanines; D010454:Peptide Termination Factors; D012333:RNA, Messenger; D012269:Ribosomal Proteins; C089187:cyanine dye 3; C085321:cyanine dye 5; C041460:peptide chain termination release factor 2; C087267:ribosome releasing factor