NCBP2 Human

Nuclear Cap Binding Protein Subunit 2 (NCBP2), also known as CBP20, is a crucial component of the nuclear cap-binding protein complex (CBC) in eukaryotic cells. This protein plays a significant role in various RNA metabolic processes, including pre-mRNA splicing, translation regulation, nonsense-mediated mRNA decay, RNA-mediated gene silencing by microRNAs (miRNAs), and mRNA export from the nucleus .

NCBP2 is a protein-coding gene that encodes a 20 kDa subunit of the CBC. The CBC is a heterodimer composed of two subunits: CBP80 and CBP20. CBP20 (NCBP2) binds to the monomethylated 5’ cap of nascent pre-mRNA in the nucleoplasm, while CBP80 ensures high-affinity cap binding . The CBC complex is involved in mRNA export from the nucleus via its interaction with ALYREF/THOC4/ALY, leading to the recruitment of the mRNA export machinery to the 5’ end of mRNA and facilitating mRNA export in a 5’ to 3’ direction through the nuclear pore .

NCBP2 contains an RNA recognition motif (RRM) domain, which is commonly found in RNA-binding proteins. This domain is responsible for the cap-binding activity of the protein. The CBC promotes pre-mRNA splicing, 3’-end processing, RNA nuclear export, and nonsense-mediated mRNA decay . Additionally, NCBP2 is involved in the export of U snRNA and intronless mRNAs from the nucleus .

NCBP2 is associated with several biological pathways, including the formation of the HIV elongation complex in the absence of HIV Tat and the transport of SLBP-independent mature mRNA . Diseases associated with NCBP2 include Seckel Syndrome, a rare genetic disorder characterized by growth retardation, microcephaly, and intellectual disability .

Human recombinant NCBP2 is produced using recombinant DNA technology, which involves inserting the NCBP2 gene into an expression vector and introducing it into a host cell, such as E. coli or yeast. The host cells then produce the NCBP2 protein, which can be purified and used for various research and therapeutic applications.