InterPro domain: IPR034148

This entry represents the RNA recognition motif (RRM) of CBP20 (also known as NCBP2). CBP20 is the small subunit of the nuclear cap binding complex (CBC), which is a conserved eukaryotic heterodimeric protein complex binding to 5'-capped polymerase II transcripts and plays a central role in the maturation of pre-mRNA and uracil-rich small nuclear RNA (U snRNA). CBP20 is most likely responsible for the binding of capped RNA [ 1 , 2 ]. It contains an RNA recognition motif (RRM) and interacts with the second and third domains of CBP80, the large subunit of CBC [ 3 ].

1. Co-crystallization of the human nuclear cap-binding complex with a m7GpppG cap analogue using protein engineering. Acta Crystallogr. D Biol. Crystallogr. 58, 2194-7
2. A cap-binding protein complex mediating U snRNA export. Nature 376, 709-12
3. Identification of the factors that interact with NCBP, an 80 kDa nuclear cap binding protein. Nucleic Acids Res. 23, 3638-41