Novel G-protein complex whose requirement is linked to the translational status of the cell

Mol Cell Biol. 2002 Apr;22(8):2564-74. doi: 10.1128/MCB.22.8.2564-2574.2002.

Abstract

G proteins, which bind and hydrolyze GTP, are involved in regulating a variety of critical cellular processes, including the process of protein synthesis. Many members of the subfamily of elongation factor class G proteins interact with the ribosome and function to regulate discrete steps during the process of protein synthesis. Despite sequence similarity to factors involved in translation, a role for the yeast Hbs1 protein has not been defined. In this work we have identified a genetic relationship between genes encoding components of the translational apparatus and HBS1. HBS1, while not essential for viability, is important for efficient growth and protein synthesis under conditions of limiting translation initiation. The identification of an Hbs1p-interacting factor, Dom34p, which shares a similar genetic relationship with components of the translational apparatus, suggests that Hbs1p and Dom34p may function as part of a complex that facilitates gene expression. Dom34p contains an RNA binding motif present in several ribosomal proteins and factors that regulate translation of specific mRNAs. Thus, Hbs1p and Dom34p may function together to help directly or indirectly facilitate the expression either of specific mRNAs or under certain cellular conditions.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Amino Acid Substitution
  • Base Sequence
  • Cell Cycle Proteins / chemistry
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism
  • Endoribonucleases
  • Fungal Proteins / chemistry
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism*
  • GTP-Binding Proteins / chemistry
  • GTP-Binding Proteins / genetics
  • GTP-Binding Proteins / metabolism*
  • Gene Deletion
  • Gene Expression
  • Genes, Fungal
  • Genetic Complementation Test
  • HSP70 Heat-Shock Proteins / chemistry
  • HSP70 Heat-Shock Proteins / genetics
  • HSP70 Heat-Shock Proteins / metabolism*
  • Macromolecular Substances
  • Peptide Elongation Factors*
  • Protein Biosynthesis*
  • RNA Processing, Post-Transcriptional
  • RNA, Fungal / genetics
  • RNA, Fungal / metabolism
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Ribosomes / metabolism
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / growth & development
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / chemistry
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*

Substances

  • Cell Cycle Proteins
  • Fungal Proteins
  • HBS1 protein, S cerevisiae
  • HSP70 Heat-Shock Proteins
  • Macromolecular Substances
  • Peptide Elongation Factors
  • RNA, Fungal
  • RNA, Messenger
  • Saccharomyces cerevisiae Proteins
  • Dom34 protein, S cerevisiae
  • Endoribonucleases
  • GTP-Binding Proteins