title: Dissociation by Pelota, Hbs1 and ABCE1 of mammalian vacant 80S ribosomes and stalled elongation complexes.
abstract: No-go decay (NGD) and non-stop decay (NSD) are eukaryotic surveillance mechanisms that target mRNAs on which elongation complexes (ECs) are stalled by, for example, stable secondary structures (NGD) or due to the absence of a stop codon (NSD). Two interacting proteins Dom34(yeast)/Pelota(mammals) and Hbs1, which are paralogues of eRF1 and eRF3, are implicated in these processes. Dom34/Hbs1 were shown to promote dissociation of stalled ECs and release of intact peptidyl-tRNA. Using an in vitro reconstitution approach, we investigated the activities of mammalian Pelota/Hbs1 and report that Pelota/Hbs1 also induced dissociation of ECs and release of peptidyl-tRNA, but only in the presence of ABCE1. Whereas Pelota and ABCE1 were essential, Hbs1 had a stimulatory effect. Importantly, ABCE1/Pelota/Hbs1 dissociated ECs containing only a limited number of mRNA nucleotides downstream of the P-site, which suggests that ABCE1/Pelota/Hbs1 would disassemble NSD complexes stalled at the 3'-end, but not pre-cleavage NGD complexes stalled in the middle of mRNA. ABCE1/Pelota/Hbs1 also dissociated vacant 80S ribosomes, which stimulated 48S complex formation, suggesting that Pelota/Hbs1 have an additional role outside of NGD.
authors: Department of Cell Biology, SUNY Downstate Medical Center, Brooklyn, NY 11203, USA.
authors: Vera P
authors: VP
authors: Pisareva
authors: Maxim A
authors: MA
authors: Skabkin
authors: Christopher U T
authors: CU
authors: Hellen
authors: Tatyana V
authors: TV
authors: Pestova
authors: Andrey V
authors: AV
authors: Pisarev
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000378:metabolism*; D000818:Animals; D004586:Electrophoresis; D004720:Endonucleases; D004926:Escherichia coli; D005822:Genetic Vectors / Q000235:genetics; D006801:Humans; D066298:In Vitro Techniques; D008840:Microfilament Proteins / Q000378:metabolism*; D009687:Nuclear Proteins; D010454:Peptide Termination Factors / Q000378:metabolism*; D020871:RNA Stability / Q000502:physiology*; D012333:RNA, Messenger / Q000378:metabolism*; D012346:RNA, Transfer, Amino Acyl / Q000378:metabolism*; D011817:Rabbits; D011994:Recombinant Proteins / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*
chemical_list: C501917:ABCE1 protein, human; D018528:ATP-Binding Cassette Transporters; D008840:Microfilament Proteins; D009687:Nuclear Proteins; D010454:Peptide Termination Factors; D012333:RNA, Messenger; D012346:RNA, Transfer, Amino Acyl; D011994:Recombinant Proteins; C087971:peptide-chain-release factor 3; C019037:tRNA, peptidyl-; D004720:Endonucleases; C550527:pelo protein, human