Nuclear cap-binding protein complex (CBC)

The **Nuclear cap-binding protein complex** (CBC), also known as the **cap-binding protein 80/20 complex** or **CBP80/20**, is a heterodimeric nuclear protein assembly composed of two subunits—cap-binding protein 20 kDa (**Cbp20**, also called NCBP2) and cap-binding protein 80 kDa (**Cbp80**, also called NCBP1)[1][2][4]. This complex binds specifically to the 7-methylguanosine (**m7G**) cap structure found at the 5' end of all eukaryotic pre-mRNAs. The CBC plays a central role in multiple aspects of nuclear mRNA metabolism including pre-mRNA splicing, polyadenylation, protection from exonucleases, and especially facilitating the export of mature messenger RNAs from the nucleus to the cytoplasm[1][2][3]. Cbp20 provides direct interaction with both RNA and the methylated guanosine cap via its RNA-recognition motif; Cbp80 stabilizes this interaction and mediates contacts with other regulatory proteins[1]. The CBC is essential for efficient gene expression by ensuring proper maturation and transport of transcripts prior to translation initiation. Dysfunction or dysregulation can contribute to disease states such as cancer or viral infection due to impaired control over gene expression[3]. If you need structured data extraction for specific fields such as interacting drugs or biomarkers not currently available in these sources, further targeted research would be required.

Other names

Cap-binding complexCBCNuclear cap-binding complexCBP80/20 complexNCBP1/NCBP2 complex