The nucle(ol)ar Tif6p and Efl1p are required for a late cytoplasmic step of ribosome synthesis

Mol Cell. 2001 Dec;8(6):1363-73. doi: 10.1016/s1097-2765(01)00403-8.

Abstract

Deletion of elongation factor-like 1 (Efl1p), a cytoplasmic GTPase homologous to the ribosomal translocases EF-G/EF-2, results in nucle(ol)ar pre-rRNA processing and pre-60S subunits export defects. Efl1p interacts genetically with Tif6p, a nucle(ol)ar protein stably associated with pre-60S subunits and required for their synthesis and nuclear exit. In the absence of Efl1p, 50% of Tif6p is relocated to the cytoplasm. In vitro, the GTPase activity of Efl1p is stimulated by 60S, and Efl1p promotes the dissociation of Tif6p-60S complexes. We propose that Tif6p binds to the pre-60S subunits in the nucle(ol)us and escorts them to the cytoplasm where the GTPase activity of Efl1p triggers a late structural rearrangement, which facilitates the release of Tif6p and its recycling to the nucle(ol)us.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biological Transport
  • Cell Division
  • Cell Nucleolus / metabolism*
  • Cell Nucleus / metabolism*
  • Conserved Sequence
  • Cytoplasm / enzymology
  • Cytoplasm / metabolism*
  • Enzyme Activation
  • GTP Phosphohydrolases / chemistry
  • GTP Phosphohydrolases / genetics
  • GTP Phosphohydrolases / metabolism*
  • Gene Deletion
  • Genes, Reporter / genetics
  • Molecular Weight
  • Phenotype
  • Protein Subunits
  • RNA Precursors / chemistry
  • RNA Precursors / genetics
  • RNA Precursors / metabolism
  • RNA Processing, Post-Transcriptional*
  • RNA, Fungal / chemistry
  • RNA, Fungal / genetics
  • RNA, Fungal / metabolism
  • RNA, Ribosomal / chemistry
  • RNA, Ribosomal / genetics
  • RNA, Ribosomal / metabolism
  • Ribosomes / chemistry
  • Ribosomes / metabolism*
  • Saccharomyces cerevisiae / cytology
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / growth & development
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / chemistry
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism

Substances

  • Protein Subunits
  • RNA Precursors
  • RNA, Fungal
  • RNA, Ribosomal
  • Saccharomyces cerevisiae Proteins
  • GTP Phosphohydrolases