EIF2G Proteins and Enzymes

eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiatortRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex.Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound toeIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round ofinitiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B