title: Heat shock-induced accumulation of translation elongation and termination factors precedes assembly of stress granules in S. cerevisiae.
abstract: In response to severe environmental stresses eukaryotic cells shut down translation and accumulate components of the translational machinery in stress granules (SGs). Since they contain mainly mRNA, translation initiation factors and 40S ribosomal subunits, they have been referred to as dominant accumulations of stalled translation preinitiation complexes. Here we present evidence that the robust heat shock-induced SGs of S. cerevisiae also contain translation elongation factors eEF3 (Yef3p) and eEF1Bγ2 (Tef4p) as well as translation termination factors eRF1 (Sup45p) and eRF3 (Sup35p). Despite the presence of the yeast prion protein Sup35 in heat shock-induced SGs, we found out that its prion-like domain is not involved in the SGs assembly. Factors eEF3, eEF1Bγ2 and eRF1 were accumulated and co-localized with Dcp2 foci even upon a milder heat shock at 42°C independently of P-bodies scaffolding proteins. We also show that eEF3 accumulations at 42°C determine sites of the genuine SGs assembly at 46°C. We suggest that identification of translation elongation and termination factors in SGs might help to understand the mechanism of the eIF2α factor phosphorylation-independent repression of translation and SGs assembly.
authors: Institute of Microbiology of AS CR, v.v.i., Prague, Czech Republic.
authors: Tomas
authors: T
authors: Grousl
authors: Pavel
authors: P
authors: Ivanov
authors: Ivana
authors: I
authors: Malcova
authors: Petr
authors: P
authors: Pompach
authors: Ivana
authors: I
authors: Frydlova
authors: Renata
authors: R
authors: Slaba
authors: Lenka
authors: L
authors: Senohrabkova
authors: Lenka
authors: L
authors: Novakova
authors: Jiri
authors: J
authors: Hasek
mesh_terms: D000595:Amino Acid Sequence; D003594:Cytoplasmic Granules / Q000378:metabolism*; D018869:Heat-Shock Response; D008969:Molecular Sequence Data; D010445:Peptide Elongation Factors / Q000737:chemistry / Q000378:metabolism*; D010454:Peptide Termination Factors / Q000737:chemistry / Q000378:metabolism*; D012261:Ribonucleoproteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism*; D013312:Stress, Physiological
chemical_list: D010445:Peptide Elongation Factors; D010454:Peptide Termination Factors; D012261:Ribonucleoproteins; D029701:Saccharomyces cerevisiae Proteins