EIF3D

Eukaryotic translation initiation factor-3 (eIF3), the largest of the eIFs, is a multiprotein complex composed of at least ten nonidentical subunits. The complex binds to the 40S ribosome and helps maintain the 40S and 60S ribosomal subunits in a dissociated state. It is also thought to play a role in the formation of the 40S initiation complex by interacting with the ternary complex of eIF2/GTP/methionyl-tRNA, and by promoting mRNA binding. The protein encoded by this gene is the major RNA binding subunit of the eIF3 complex. [provided by RefSeq, Jul 2008]

Full Name

Eukaryotic Translation Initiation Factor 3 Subunit D

Research Area

mRNA cap-binding component of the eukaryotic translation initiation factor 3 (eIF-3) complex, a complex required for several steps in the initiation of protein synthesis of a specialized repertoire of mRNAs (PubMed:27462815).

The eIF-3 complex associates with the 40S ribosome and facilitates the recruitment of eIF-1, eIF-1A, eIF-2:GTP:methionyl-tRNAi and eIF-5 to form the 43S pre-initiation complex (43S PIC). The eIF-3 complex stimulates mRNA recruitment to the 43S PIC and scanning of the mRNA for AUG recognition. The eIF-3 complex is also required for disassembly and recycling of post-termination ribosomal complexes and subsequently prevents premature joining of the 40S and 60S ribosomal subunits prior to initiation (PubMed:18599441, PubMed:25849773).

The eIF-3 complex specifically targets and initiates translation of a subset of mRNAs involved in cell proliferation, including cell cycling, differentiation and apoptosis, and uses different modes of RNA stem-loop binding to exert either translational activation or repression (PubMed:25849773).

In the eIF-3 complex, EIF3D specifically recognizes and binds the 7-methylguanosine cap of a subset of mRNAs (PubMed:27462815).

(Microbial infection) In case of FCV infection, plays a role in the ribosomal termination-reinitiation event leading to the translation of VP2 (PubMed:18056426).

Biological Process

Cap-dependent translational initiation Source: UniProtKB
Formation of cytoplasmic translation initiation complex Source: UniProtKB-UniRule
IRES-dependent viral translational initiation Source: UniProtKB
Positive regulation of mRNA binding Source: ParkinsonsUK-UCL
Positive regulation of translation Source: ParkinsonsUK-UCL
Translational initiation Source: UniProtKB
Viral translational termination-reinitiation Source: UniProtKB

Cellular Location

Cytoplasm

Involvement in disease

Defects in EIF3D are associated with some cancers, such as prostate, breast and colon cancers. Disease susceptibility may be associated with variants affecting the gene represented in this entry. Down-regulation inhibits proliferation of cancers (PubMed:25370813, PubMed:25322666, PubMed:25682860, PubMed:26617750, PubMed:26008152, PubMed:26036682, PubMed:27035563).