PROTEIN-SYNTHESIS IN EUKARYOTIC ORGANISMS - NEW INSIGHTS INTO THE FUNCTION OF TRANSLATION INITIATION-FACTOR EIF-3

The pathway for initiation of protein synthesis in eukaryotic cells ha s been defined and refined over the last 25 years using purified compo nents and in vitro reconstituted systems. More recently, powerful gene tic analysis in yeast has proved useful in unraveling aspects of trans lation inherently more difficult to address by strictly biochemical ap proaches. One area in particular is the functional analysis of multi-s ubunit protein factors, termed eukaryotic initiation factors (elFs), t hat play an essential role in translation initiation, elF-3, the most structurally complex of the elFs, has until recently eluded this appro ach. The identification of the yeast GCD10 gene as the structural gene for the zeta subunit of yeast elF-3((1)) and the analysis of mutant p henotypes has opened the door to the genetic dissection of the elF-3 p rotein complex.