Biogenesis of cytosolic ribosomes requires the essential iron-sulphur protein Rli1p and mitochondria

EMBO J. 2005 Feb 9;24(3):589-98. doi: 10.1038/sj.emboj.7600541. Epub 2005 Jan 20.

Abstract

Mitochondria perform a central function in the biogenesis of cellular iron-sulphur (Fe/S) proteins. It is unknown to date why this biosynthetic pathway is indispensable for life, the more so as no essential mitochondrial Fe/S proteins are known. Here, we show that the soluble ATP-binding cassette (ABC) protein Rli1p carries N-terminal Fe/S clusters that require the mitochondrial and cytosolic Fe/S protein biogenesis machineries for assembly. Mutations in critical cysteine residues of Rli1p abolish association with Fe/S clusters and lead to loss of cell viability. Hence, the essential character of Fe/S clusters in Rli1p explains the indispensable character of mitochondria in eukaryotes. We further report that Rli1p is associated with ribosomes and with Hcr1p, a protein involved in rRNA processing and translation initiation. Depletion of Rli1p causes a nuclear export defect of the small and large ribosomal subunits and subsequently a translational arrest. Thus, ribosome biogenesis and function are intimately linked to the crucial role of mitochondria in the maturation of the essential Fe/S protein Rli1p.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP-Binding Cassette Transporters / chemistry
  • ATP-Binding Cassette Transporters / genetics
  • ATP-Binding Cassette Transporters / metabolism*
  • Amino Acid Sequence
  • Base Sequence
  • Biological Transport, Active
  • Cytosol / metabolism
  • DNA, Fungal / genetics
  • Genes, Fungal
  • Iron-Sulfur Proteins / chemistry
  • Iron-Sulfur Proteins / genetics
  • Iron-Sulfur Proteins / metabolism*
  • Mitochondria / metabolism*
  • Molecular Sequence Data
  • Mutagenesis, Site-Directed
  • Peptide Initiation Factors / genetics
  • Peptide Initiation Factors / metabolism
  • Protein Biosynthesis
  • Protein Structure, Tertiary
  • Ribosomes / metabolism*
  • Saccharomyces cerevisiae / cytology
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins / chemistry
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Sequence Homology, Amino Acid

Substances

  • ATP-Binding Cassette Transporters
  • DNA, Fungal
  • HCR1 protein, S cerevisiae
  • Iron-Sulfur Proteins
  • Peptide Initiation Factors
  • RLI1 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins