Translation Initiation Factors eIF3 and HCR1 Control Translation Termination and Stop Codon Read-Through in Yeast Cells

0425640 - MBÚ 2014 RIV US eng J - Journal Article
Beznosková, Petra - Cuchalová, Lucie - Wagner, Susan - Shoemaker, Ch. J. - Gunišová, Stanislava - von der Haar, T. - Valášek, Leoš Shivaya
Translation Initiation Factors eIF3 and HCR1 Control Translation Termination and Stop Codon Read-Through in Yeast Cells.
PLoS Genetics. Roč. 9, č. 11 (2013). ISSN 1553-7404. E-ISSN 1553-7404
R&D Projects: GA ČR(CZ) GBP305/12/G034
Institutional support: RVO:61388971
Keywords : RNA RECOGNITION MOTIF * MESSENGER-RNA * IN-VIVO
Subject RIV: EB - Genetics ; Molecular Biology
Impact factor: 8.167, year: 2013

Translation is divided into initiation, elongation, termination and ribosome recycling. Earlier work implicated several eukaryotic initiation factors (eIFs) in ribosomal recycling in vitro. Here, we uncover roles for HCR1 and eIF3 in translation termination in vivo. A substantial proportion of eIF3, HCR1 and eukaryotic release factor 3 (eRF3) but not eIF5 (a well-defined "initiation-specific" binding partner of eIF3) specifically co-sediments with 80S couples isolated from RNase-treated heavy polysomes in an eRF1-dependent manner, indicating the presence of eIF3 and HCR1 on terminating ribosomes. eIF3 and HCR1 also occur in ribosome-and RNA-free complexes with both eRFs and the recycling factor ABCE1/RLI1. Several eIF3 mutations reduce rates of stop codon read-through and genetically interact with mutant eRFs. In contrast, a slow growing deletion of hcr1 increases read-through and accumulates eRF3 in heavy polysomes in a manner suppressible by overexpressed ABCE1/RLI1. Based on these and other findings we propose that upon stop codon recognition, HCR1 promotes eRF3.GDP ejection from the post-termination complexes to allow binding of its interacting partner ABCE1/RLI1
Permanent Link: http://hdl.handle.net/11104/0231488