Eukaryotic Translation Initiation Factor 2B5 (EIF2B5)

EIF2B5 encodes one of five subunits of eukaryotic translation initiation factor 2B (EIF2B), a GTP exchange factor for eukaryotic initiation factor 2 and an essential regulator for protein synthesis. Mutations in this gene and the genes encoding other EIF2B subunits have been associated with leukoencephalopathy with vanishing white matter.The predicted 721-amino acid protein migrates at approximately 84 kD by SDS-PAGE. The authors stated that the N-terminal region of eIF2B-epsilon contains a putative nucleotide-binding domain that may be directly involved in nucleotide exchange.A significant decrease of 20 to 70% in GEF activity was observed in all mutated cells, and the extent of the decrease correlated with age at onset of disease.