Translation termination and its regulation in eukaryotes: Recent insights provided by studies in yeast

In protein synthesis, the arrival of one or other of the three stop codons in the ribosomal A-site triggers the binding of a release factor (RF) to th e ribosome and subsequent polypeptide chain release. In eukaryotes, the RF is composed of two proteins, eRF1 and eRF3. eRF1 is responsible for the hyd rolysis of the peptidyl-tRNA, while eRF3 provides a GTP-dependent function, although its precise role remains to be defined. Recent findings on transl ation termination and its regulation from studies in the yeast Saccharomyce s cerevisiae are reviewed and the potential role of eRF3 is discussed.