Non-FG mediated transport of the large pre-ribosomal subunit through the nuclear pore complex by the mRNA export factor Gle2

Nucleic Acids Res. 2013 Sep;41(17):8266-79. doi: 10.1093/nar/gkt675. Epub 2013 Jul 31.

Abstract

Multiple export receptors passage bound pre-ribosomes through nuclear pore complexes (NPCs) by transiently interacting with the Phe-Gly (FG) meshwork of their transport channels. Here, we reveal how the non-FG interacting yeast mRNA export factor Gly-Leu-FG lethal 2 (Gle2) functions in the export of the large pre-ribosomal subunit (pre-60S). Structure-guided studies uncovered conserved platforms used by Gle2 to export pre-60S: an uncharacterized basic patch required to bind pre-60S, and a second surface that makes non-FG contacts with the nucleoporin Nup116. A basic patch mutant of Gle2 is able to function in mRNA export, but not pre-60S export. Thus, Gle2 provides a distinct interaction platform to transport pre-60S to the cytoplasm. Notably, Gle2's interaction platforms become crucial for pre-60S export when FG-interacting receptors are either not recruited to pre-60S or are impaired. We propose that large complex cargos rely on non-FG as well as FG-interactions for their efficient translocation through the nuclear pore complex channel.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Active Transport, Cell Nucleus
  • Amino Acid Sequence
  • Binding Sites
  • Molecular Sequence Data
  • Mutation
  • Nuclear Pore / metabolism*
  • Nuclear Pore Complex Proteins / chemistry
  • Nuclear Pore Complex Proteins / genetics
  • Nuclear Pore Complex Proteins / metabolism*
  • RNA, Messenger / metabolism
  • Ribosome Subunits, Large, Eukaryotic / metabolism*
  • Saccharomyces cerevisiae Proteins / chemistry
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Sequence Alignment

Substances

  • GLE2 protein, S cerevisiae
  • Nuclear Pore Complex Proteins
  • RNA, Messenger
  • Saccharomyces cerevisiae Proteins