HUMAN PROTEIN-SYNTHESIS INITIATION-FACTOR EIF-4-GAMMA IS ENCODED BY ASINGLE-GENE (EIF4G) THAT MAPS TO CHROMOSOME 3Q27-QTER

Messenger RNA binding to the ribosome, the rate-limiting step in eukar yotic protein synthesis, is catalyzed by the eIF-4 group of initiation factors. These factors collectively bind to the m(7)GTP-containing ca p of mRNA and unwind mRNA secondary structure at the expense of ATP. O ne member of the group, eIF-4 gamma, is the target for proteolytic cle avage during picornavirus infection, an event that is thought to be re sponsible for the inhibition of host cellular mRNA translation. Human eIF-4 gamma migrates as a cluster of polypeptides in the range of 200- 220 kDa during SDS-PAGE, raising the possibility that it is a family o f proteins encoded by separate genes. In this study, we present genomi c Southern blotting results which indicate that there is only a single gene, here designated EIF4G. Furthermore, we have employed a PCR appr oach to map EIF4G to chromosome 3q27-qter. (C) 1995 Academic Press, In c.