cd12402: RRM_eIF4B (this model, PSSM-Id:240848 is obsolete and has been replaced by 409836)
RNA recognition motif in eukaryotic translation initiation factor 4B (eIF-4B) and similar proteins
This subfamily corresponds to the RRM of eIF-4B, a multi-domain RNA-binding protein that has been primarily implicated in promoting the binding of 40S ribosomal subunits to mRNA during translation initiation. It contains two RNA-binding domains; the N-terminal well-conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), binds the 18S rRNA of the 40S ribosomal subunit and the C-terminal basic domain (BD), including two arginine-rich motifs (ARMs), binds mRNA during initiation, and is primarily responsible for the stimulation of the helicase activity of eIF-4A. eIF-4B also contains a DRYG domain (a region rich in Asp, Arg, Tyr, and Gly amino acids) in the middle, which is responsible for both, self-association of eIF-4B and binding to the p170 subunit of eIF3. Additional research indicates that eIF-4B can interact with the poly(A) binding protein (PABP) in mammalian cells, which can stimulate both, the eIF-4B-mediated activation of the helicase activity of eIF-4A and binding of poly(A) by PABP. eIF-4B has also been shown to interact specifically with the internal ribosome entry sites (IRES) of several picornaviruses which facilitate cap-independent translation initiation.
Jiyao W et al.(2023). "The conserved domain database in 2023.",