Eukaryotic translation initiation factor 3 subunit G, N-terminal (IPR024675)

Short name: eIF3g_N

Overlapping homologous superfamilies


Domain relationships



At least eleven different protein factors are involved in initiation of protein synthesis in eukaryotes. Binding of initiator tRNA and mRNA to the 40S subunit requires the presence of the translation initiation factors eIF-2 and eIF-3, with eIF-3 being particularly important for 80S ribosome dissociation and mRNA binding [PMID: 1742346]. eIF-3 is the most complex translation inititation factor, consisting of about 13 putative subunits and having a molecular weight of between 550 - 700 kDa in mammalian cells. Subunits are designated eIF-3a - eIF-3m; the large number of subunits means that the interactions between the individual subunits that make up the eIF-3 complex are complex and varied.

eIF-3G (also termed eIF-3 subunit 4, eIF-3-delta, eIF3-p42, or eIF3-p44) is the RNA-binding subunit of eIF3. Subunit eIF-3G binds 18 S rRNA and beta-globin mRNA, and therefore appears to be a nonspecific RNA-binding protein. It is one of the cytosolic targets and interacts with mature apoptosis-inducing factor (AIF). The yeast orthologue is known as eIF3-p33; it plays an important role in the initiation phase of protein synthesis in yeast. It binds both mRNA and rRNA fragments due to an RNA recognition motif near its C terminus [PMID: 17581632, PMID: 9362495, PMID: 10085088, PMID: 20679478, PMID: 16322461, PMID: 18599441, PMID: 17322308, PMID: 16766523, PMID: 17094969, PMID: 15703437, PMID: 14688252, PMID: 14519125, PMID: 9973622, PMID: 9822659].

This entry represents a domain of approximately 130 amino acids in length found at the N terminus of eukaryotic translation initiation factor 3 subunit G. This domain is commonly found in association with the RNA recognition domain PF00076.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.