FUNCTION : EIF-2 FUNCTIONS IN THE EARLY STEPS OF PROTEIN SYNTHESIS BY FORMING A TERNARY COMPLEX WITH GTP AND INITIATOR TRNA. 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 TO EIF-2 AND RELEASE OF AN EIF-2-GDP BINARY COMPLEX. IN ORDER FOR EIF-2 TO RECYCLE AND CATALYZE ANOTHER ROUND OF INITIATION, THE GDP BOUND TO EIF-2 MUST EXCHANGE WITH GTP BY WAY OF A REACTION CATALYZED BY EIF-2B. SUBUNIT : Heterotrimer composed of an alpha, a beta, and a gamma chain. SIMILARITY : BELONGS TO THE GTP-BINDING ELONGATION FACTOR FAMILY. EIF2G SUBFAMILY. |
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19-MAR-03
Last Update 20-Mar-03