2ob7

Publication Abstract from PubMed

A eubacterial ribosome stalled on a defective mRNA can be released through a quality control mechanism referred to as trans-translation, which depends on the coordinating binding actions of transfer-messenger RNA, small protein B, and ribosome protein S1. By means of cryo-electron microscopy, we obtained a map of the complex composed of a stalled ribosome and small protein B, which appears near the decoding center. This result suggests that, when lacking a codon, the A-site on the small subunit is a target for small protein B. To investigate the role of S1 played in trans-translation, we obtained a cryo-electron microscopic map, including a stalled ribosome, transfer-messenger RNA, and small protein Bs but in the absence of S1. In this complex, several connections between the 30 S subunit and transfer-messenger RNA that appear in the +S1 complex are no longer found. We propose the unifying concept of scaffolding for the roles of small protein B and S1 in binding of transfer-messenger RNA to the ribosome during trans-translation, and we infer a pathway of sequential binding events in the initial phase of trans-translation.

Scaffolding as an organizing principle in trans-translation. The roles of small protein B and ribosomal protein S1.,Gillet R, Kaur S, Li W, Hallier M, Felden B, Frank J J Biol Chem. 2007 Mar 2;282(9):6356-63. Epub 2006 Dec 19. PMID:17179154^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.