3j16
From Proteopedia
Models of ribosome-bound Dom34p and Rli1p and their ribosomal binding partners
Structural highlights
FunctionDOM34_YEAST Involved in protein translation. Together with HBS1, may function in recognizing stalled ribosomes and triggering endonucleolytic cleavage of the mRNA, a mechanism to release non-functional ribosomes and degrade damaged mRNAs. The complex formed by DOM34 and HBS1 has ribonuclease activity towards double-stranded RNA substrates, but does not cleave single-stranded RNA. Acts as endonuclease; has no exonuclease activity. Increases the affinity of HBS1 for GTP, but nor for GDP. Promotes G1 progression and differentiation and is involved in mitotic and meiotic cell divisions.[1] [2] [3] Publication Abstract from PubMedRibosome-driven protein biosynthesis is comprised of four phases: initiation, elongation, termination and recycling. In bacteria, ribosome recycling requires ribosome recycling factor and elongation factor G, and several structures of bacterial recycling complexes have been determined. In the eukaryotic and archaeal kingdoms, however, recycling involves the ABC-type ATPase ABCE1 and little is known about its structural basis. Here we present cryo-electron microscopy reconstructions of eukaryotic and archaeal ribosome recycling complexes containing ABCE1 and the termination factor paralogue Pelota. These structures reveal the overall binding mode of ABCE1 to be similar to canonical translation factors. Moreover, the iron-sulphur cluster domain of ABCE1 interacts with and stabilizes Pelota in a conformation that reaches towards the peptidyl transferase centre, thus explaining how ABCE1 may stimulate peptide-release activity of canonical termination factors. Using the mechanochemical properties of ABCE1, a conserved mechanism in archaea and eukaryotes is suggested that couples translation termination to recycling, and eventually to re-initiation. Structural basis of highly conserved ribosome recycling in eukaryotes and archaea.,Becker T, Franckenberg S, Wickles S, Shoemaker CJ, Anger AM, Armache JP, Sieber H, Ungewickell C, Berninghausen O, Daberkow I, Karcher A, Thomm M, Hopfner KP, Green R, Beckmann R Nature. 2012 Feb 22;482(7386):501-6. doi: 10.1038/nature10829. PMID:22358840[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| ||||||||||||||||||||
