title: Let's see how tmRNA rescues a stuck ribosome.
abstract: In the current issue, Weis et al (2010a) and Fu et al (2010) provide cryo-electron microscopy snapshots of different states of the bacterial ribosome-rescuing complex with tmRNA. This regulatory RNA molecule remarkably carries both tRNA- and mRNA-like elements that have to move through the ribosome machinery when it is stalled on an mRNA lacking a termination codon. The comparison of three intermediate states gives novel insights into the mechanism of tmRNA translocation and transient accommodation on the ribosome, and into trans-translation—the template switching from a defective mRNA to the short coding region of the tmRNA, which allows rescuing the stuck ribosome.
authors.affiliation: Department of Structural Biology and Genomics, Centre National de la Recherche Scientifique, Institute of Genetics and of Molecular and Cellular Biology, Université de Strasbourg, Illkirch, France. klaholz@igbmc.fr
authors.forename: Bruno P
authors.initials: BP
authors.lastname: Klaholz
mesh_terms: D020285:Cryoelectron Microscopy; D004926:Escherichia coli / Q000737:chemistry / Q000378:metabolism*; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D016366:Open Reading Frames; D014176:Protein Biosynthesis; D012329:RNA, Bacterial / Q000737:chemistry / Q000378:metabolism*; D012270:Ribosomes / Q000737:chemistry / Q000378:metabolism*; D016963:Thermus thermophilus / Q000737:chemistry / Q000378:metabolism*
chemical_list: D012329:RNA, Bacterial; C096222:tmRNA