The role of ABCE1 in eukaryotic posttermination ribosomal recycling

Mol Cell. 2010 Jan 29;37(2):196-210. doi: 10.1016/j.molcel.2009.12.034.


After termination, eukaryotic 80S ribosomes remain associated with mRNA, P-site deacylated tRNA, and release factor eRF1 and must be recycled by dissociating these ligands and separating ribosomes into subunits. Although recycling of eukaryotic posttermination complexes (post-TCs) can be mediated by initiation factors eIF3, eIF1, and eIF1A (Pisarev et al., 2007), this energy-free mechanism can function only in a narrow range of low Mg(2+) concentrations. Here, we report that ABCE1, a conserved and essential member of the ATP-binding cassette (ABC) family of proteins, promotes eukaryotic ribosomal recycling over a wide range of Mg(2+) concentrations. ABCE1 dissociates post-TCs into free 60S subunits and mRNA- and tRNA-bound 40S subunits. It can hydrolyze ATP, GTP, UTP, and CTP. NTP hydrolysis by ABCE1 is stimulated by post-TCs and is required for its recycling activity. Importantly, ABCE1 dissociates only post-TCs obtained with eRF1/eRF3 (or eRF1 alone), but not post-TCs obtained with puromycin in eRF1's absence.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP-Binding Cassette Transporters / physiology*
  • Adenosine Triphosphate / metabolism
  • Cytidine Triphosphate / metabolism
  • Eukaryotic Initiation Factors / physiology
  • Guanosine Triphosphate / metabolism
  • Humans
  • Magnesium / metabolism
  • Peptide Termination Factors / metabolism
  • Protein Biosynthesis
  • Ribosome Subunits / metabolism
  • Ribosomes / metabolism*
  • Uridine Triphosphate / metabolism


  • ABCE1 protein, human
  • ATP-Binding Cassette Transporters
  • ETF1 protein, human
  • Eukaryotic Initiation Factors
  • Peptide Termination Factors
  • Cytidine Triphosphate
  • Guanosine Triphosphate
  • Adenosine Triphosphate
  • Magnesium
  • Uridine Triphosphate