Nuclear Cap Binding Protein Subunit 2 (NCBP2)

NCBP2 is a component of the nuclear cap-binding protein complex (CBC), which binds to the monomethylated 5' cap of nascent pre-mRNA in the nucleoplasm. The encoded protein has an RNP domain commonly found in RNA binding proteins, and contains the cap-binding activity. The CBC promotes pre-mRNA splicing, 3'-end processing, RNA nuclear export, and nonsense-mediated mRNA decay. Multiple transcript variants encoding different isoforms have been found for this gene. Sequence analysis of the deduced 156-amino acid NCBP2 protein, which shares 84% amino acid identity with the Xenopus Ncbp2 protein, predicted that it contains an RNP motif with highly conserved RNP1 and RNP2 domains. Northern blot analysis detected a major 2.0- and a minor 0.8-kb NCBP2 transcript.