eIF-2B gamma subunit, C-terminal Left-handed parallel beta-Helix (LbH) domain: eIF-2B is a eukaryotic translation initiator, a guanine nucleotide exchange factor (GEF) composed of five different subunits (alpha, beta, gamma, delta and epsilon). eIF2B is important for regenerating GTP-bound eIF2 during the initiation process. This event is obligatory for eIF2 to bind initiator methionyl-tRNA, forming the ternary initiation complex. The eIF-2B gamma subunit contains an N-terminal domain that resembles a dinucleotide-binding Rossmann fold and a C-terminal LbH domain with 4 turns, each containing three imperfect tandem repeats of a hexapeptide repeat motif (X-[STAV]-X-[LIV]-[GAED]-X). The epsilon and gamma subunits form the catalytic subcomplex of eIF-2B, which binds eIF2 and catalyzes guanine nucleotide exchange.