Gene Ontology Help

Eukaryotic translation initiation factor 2B complex Overview

GO Annotations consist of four mandatory components: a gene product, a term from one of the three Gene Ontology (GO) controlled vocabularies (Molecular Function, Biological Process, and Cellular Component), a reference, and an evidence code.


Summary
Plays a critical regulatory role in eukaryotic translation initiation. Acts as a guanine nucleotide exchange factor (GEF) catalyzing the exchange of GDP on eIF2-GDP for GTP, thus reactivating eIF2 (CPX-427) and allowing subsequent rounds of translation initiation. This activity is inhibited by the when phosphorylated eIF2 (alpha subunit) binds to eIF2B. Phosphorylation of eIF2 occurs in response to nutrient starvation and thus prevents further protein synthesis. eIF2B also acts as a GDP dissociation inhibitor (GDI) displacement factor that can recruit eIF2 from the eIF2.GDP/eIF5 GDI complex prior to GEF action.
GO Slim Terms

The yeast GO Slim terms are higher level terms that best represent the major S. cerevisiae biological processes, functions, and cellular components. The GO Slim terms listed here are the broader parent terms for the specific terms to which this gene product is annotated, and thus represent the more general processes, functions, and components in which it is involved.

enzyme regulator activity, guanyl-nucleotide exchange factor activity, translation factor activity, RNA binding, regulation of translation