EIF3B Monoclonal antibody

EIF3B, also named Eukaryotic translation initiation factor 3 subunit B, is an 814 amino acid protein, which contains 1 RRM (RNA recognition motif) domain and 8 WD repeats and belongs to the eIF-3 subunit B family. EIF3B as an RNA-binding component of the eukaryotic translation initiation factor 3 (eIF-3) complex, is required for several steps in the initiation of protein synthesis. 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. 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. The calculated molecular weight of EIF3B is 93 kDa, but the phosphorylated EIF3B protein is about 115 kDa.