The translation machinery and 70 kd heat shock protein cooperate in protein synthesis

Cell. 1992 Oct 2;71(1):97-105. doi: 10.1016/0092-8674(92)90269-i.

Abstract

The function of the yeast SSB 70 kd heatshock proteins (hsp70s) was investigated by a variety of approaches. The SSB hsp70s (Ssb1/2p) are associated with translating ribosomes. This association is disrupted by puromycin, suggesting that Ssb1/2p may bind directly to the nascent polypeptide. Mutant ssb1 ssb2 strains grow slowly, contain a low number of translating ribosomes, and are hypersensitive to several inhibitors of protein synthesis. The slow growth phenotype of ssb1 ssb2 mutants is suppressed by increased copy number of a gene encoding a novel translation elongation factor 1 alpha (EF-1 alpha)-like protein. We suggest that cytosolic hsp70 aids in the passage of the nascent polypeptide chain through the ribosome in a manner analogous to the role played by organelle-localized hsp70 in the transport of proteins across membranes.

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Fungal Proteins / biosynthesis
  • Fungal Proteins / chemistry
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism*
  • GTP-Binding Proteins*
  • HSP70 Heat-Shock Proteins*
  • Heat-Shock Proteins / chemistry
  • Heat-Shock Proteins / metabolism*
  • Molecular Sequence Data
  • Peptide Elongation Factor 1
  • Peptide Elongation Factors / chemistry
  • Peptide Elongation Factors / genetics
  • Peptide Elongation Factors / metabolism*
  • Protein Biosynthesis / drug effects
  • Protein Biosynthesis / physiology*
  • Puromycin / pharmacology
  • Ribonucleoproteins / chemistry
  • Ribonucleoproteins / genetics
  • Ribonucleoproteins / metabolism*
  • Ribosomes / metabolism*
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae Proteins*

Substances

  • Fungal Proteins
  • HBS1 protein, S cerevisiae
  • HSP70 Heat-Shock Proteins
  • Heat-Shock Proteins
  • Peptide Elongation Factor 1
  • Peptide Elongation Factors
  • Ribonucleoproteins
  • Saccharomyces cerevisiae Proteins
  • Puromycin
  • GTP-Binding Proteins

Associated data

  • GENBANK/L04285
  • GENBANK/M98437
  • GENBANK/S47136
  • GENBANK/S47137
  • GENBANK/S47164
  • GENBANK/S47165
  • GENBANK/S47166
  • GENBANK/S47167
  • GENBANK/S47168
  • GENBANK/S72771