NCBP2: Nuclear Cap-Binding Protein Subunit 2
A key component of the cap-binding complex involved in RNA processing and export
Gene Information Card
| Symbol | NCBP2 |
|---|---|
| Full Name | Nuclear Cap-Binding Protein Subunit 2 |
| Gene Type | Protein coding |
| Chromosomal Location | 3q29 |
| NCBI Gene ID | 22916 ncbi.nlm.nih.gov/gene/22916 |
| Ensembl ID | ENSG00000114503 |
| UniProt ID | P52298 |
| OMIM ID | 605133 |
| HGNC ID | 7659 |
| Aliases | CBP20, NIP1, CBC2 |
Description
NCBP2 encodes the small subunit (CBP20) of the nuclear cap-binding complex (CBC), which binds to the 5' cap of pre-mRNAs and plays essential roles in pre-mRNA splicing, polyadenylation, nuclear export, and nonsense-mediated decay. The CBC heterodimer consists of NCBP1 (CBP80) and NCBP2 (CBP20). NCBP2 directly contacts the methylated cap structure. The gene is located on chromosome 3q29 and is ubiquitously expressed.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Neurodevelopmental disorder with microcephaly and seizures | Loss-of-function mutations in NCBP2 disrupt CBC function, impairing RNA processing and leading to neuronal defects | ClinVar, OMIM |
| Colorectal cancer | NCBP2 overexpression correlates with poor prognosis; may promote tumorigenesis via altered RNA metabolism | COSMIC, literature |
| Breast cancer | NCBP2 amplification observed in some subtypes; potential role in mRNA export dysregulation | COSMIC |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Testis | 28.5 | High |
| Brain | 18.2 | Medium |
| Heart | 15.1 | Medium |
| Liver | 12.3 | Medium |
| Lung | 10.8 | Medium |
| Kidney | 9.5 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK293 | 22.4 | Embryonic kidney; high expression |
| HeLa | 19.7 | Cervical carcinoma; moderate-high |
| K562 | 14.2 | Leukemia; moderate |
| HepG2 | 11.6 | Hepatocellular carcinoma; moderate |
| A549 | 9.8 | Lung carcinoma; low-moderate |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1A>G (p.Met1?) | Start loss | Rare | Loss of protein; associated with neurodevelopmental disorder |
| c.208C>T (p.Arg70Trp) | Missense | <0.01% | Impaired cap binding; likely pathogenic |
| c.334G>A (p.Gly112Ser) | Missense | <0.01% | Uncertain significance |
| Amplification | Copy number gain | Variable | Observed in breast cancer; potential gain-of-function |
Mutation functional classification
Loss of Function (LOF)
Start-loss and missense mutations (e.g., p.Met1?, p.Arg70Trp) reduce or abolish cap-binding activity, leading to defective RNA processing and neurodevelopmental phenotypes.
Gain of Function (GOF)
Amplification of NCBP2 in cancers may increase CBC assembly and enhance mRNA export, promoting cell proliferation.
Dominant Negative (DN)
Not reported for NCBP2; mutations are typically recessive or haploinsufficient.
View complete mutation data：
Gene Ontology (GO)
Pathways
• mRNA Splicing - Major Pathway (Reactome: R-HSA-72163)
• Transport of Mature mRNA derived from an Intron-Containing Transcript (Reactome: R-HSA-159236)
• Nonsense-Mediated Decay (Reactome: R-HSA-927802)
Protein Summary
NCBP2 (CBP20) is a 156-amino-acid protein that forms the small subunit of the nuclear cap-binding complex. It contains an RNA recognition motif (RRM) that directly binds the 7-methylguanosine cap of RNA polymerase II transcripts. The protein is essential for efficient pre-mRNA splicing, polyadenylation, and nuclear export. It also participates in nonsense-mediated decay by recruiting UPF factors. NCBP2 is highly conserved across eukaryotes and is ubiquitously expressed.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| NCBP2AS2 Knockout HEK293 Cell Line | EDJ-KQ11388 | Human | 152217 | Details Get a Quote |
| NCBP2L Knockout HEK293 Cell Line | EDJ-KQ14388 | Human | 392517 | Details Get a Quote |
| NCBP2AS2 Knockout A-549 Cell Line | EDJ-KQ39594 | Human | 152217 | Details Get a Quote |
| NCBP2AS2 Knockout HCT 116 Cell Line | EDJ-KQ39595 | Human | 152217 | Details Get a Quote |
| NCBP2AS2 Knockout HeLa Cell Line | EDJ-KQ39596 | Human | 152217 | Details Get a Quote |
