Search Results
Overview
| Uniprot ID | Q09161 |
|---|---|
| Protein Name | Nuclear cap-binding protein subunit 1 |
| Gene Name | NCBP1 |
| Organism | Homo sapiens |
Kla Sites from experimental identification
| Position | Flanking peptide |
|---|---|
| 17 | NDGGQPHKRRKTSDA |
| 20 | GQPHKRRKTSDANET |
| 486 | ANPTCIYKYGDESSN |
| 684 | DDRSSDRKDGVLEEQ |
Function
Component of the cap-binding complex (CBC), which binds cotranscriptionally to the 5'-cap of pre-mRNAs and is involved in various processes such as pre-mRNA splicing, translation regulation, nonsense-mediated mRNA decay, RNA-mediated gene silencing (RNAi) by microRNAs (miRNAs) and mRNA export. 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 to mRNA export in a 5' to 3' direction through the nuclear pore. The CBC complex is also involved in mediating U snRNA and intronless mRNAs export from the nucleus. The CBC complex is essential for a pioneer round of mRNA translation, before steady state translation when the CBC complex is replaced by cytoplasmic cap-binding protein eIF4E. The pioneer round of mRNA translation mediated by the CBC complex plays a central role in nonsense-mediated mRNA decay (NMD), NMD only taking place in mRNAs bound to the CBC complex, but not on eIF4E-bound mRNAs. The CBC complex enhances NMD in mRNAs containing at least one exon-junction complex (EJC) via its interaction with UPF1, promoting the interaction between UPF1 and UPF2. The CBC complex is also involved in 'failsafe' NMD, which is independent of the EJC complex, while it does not participate in Staufen-mediated mRNA decay (SMD). During cell proliferation, the CBC complex is also involved in microRNAs (miRNAs) biogenesis via its interaction with SRRT/ARS2 and is required for miRNA-mediated RNA interference. The CBC complex also acts as a negative regulator of PARN, thereby acting as an inhibitor of mRNA deadenylation. In the CBC complex, NCBP1/CBP80 does not bind directly capped RNAs (m7GpppG-capped RNA) but is required to stabilize the movement of the N-terminal loop of NCBP2/CBP20 and lock the CBC into a high affinity cap-binding state with the cap structure. Associates with NCBP3 to form an alternative cap-binding complex (CBC) which plays a key role in mRNA export and is particularly important in cellular stress situations such as virus infections. The conventional CBC with NCBP2 binds both small nuclear RNA (snRNA) and messenger (mRNA) and is involved in their export from the nucleus whereas the alternative CBC with NCBP3 does not bind snRNA and associates only with mRNA thereby playing a role only in mRNA export. NCBP1/CBP80 is required for cell growth and viability (PubMed:26382858)
Protein Sequence
Gene Ontology
| Classification | GO ID | Description |
|---|---|---|
| Cellular Component | GO:0005846 | nuclear cap binding complex |
| Cellular Component | GO:0005737 | cytoplasm |
| Cellular Component | GO:0005829 | cytosol |
| Cellular Component | GO:0005654 | nucleoplasm |
| Cellular Component | GO:0005634 | nucleus |
| Cellular Component | GO:1990904 | ribonucleoprotein complex |
| Cellular Component | GO:0034518 | RNA cap binding complex |
| Molecular Function | GO:0060090 | molecular adaptor activity |
| Molecular Function | GO:0003729 | mRNA binding |
| Molecular Function | GO:0000340 | RNA 7-methylguanosine cap binding |
| Molecular Function | GO:0003723 | RNA binding |
| Molecular Function | GO:0000339 | RNA cap binding |
| Biological Process | GO:0006370 | 7-methylguanosine mRNA capping |
| Biological Process | GO:0000380 | alternative mRNA splicing, via spliceosome |
| Biological Process | GO:0002191 | cap-dependent translational initiation |
| Biological Process | GO:0051607 | defense response to virus |
| Biological Process | GO:0008334 | histone mRNA metabolic process |
| Biological Process | GO:0035195 | miRNA-mediated post-transcriptional gene silencing |
| Biological Process | GO:0031124 | mRNA 3'-end processing |
| Biological Process | GO:0006406 | mRNA export from nucleus |
| Biological Process | GO:0016071 | mRNA metabolic process |
| Biological Process | GO:0000398 | mRNA splicing, via spliceosome |
| Biological Process | GO:0042789 | mRNA transcription by RNA polymerase II |
| Biological Process | GO:0000184 | nuclear-transcribed mRNA catabolic process, nonsense-mediated decay |
| Biological Process | GO:0030307 | positive regulation of cell growth |
| Biological Process | GO:0031442 | positive regulation of mRNA 3'-end processing |
| Biological Process | GO:0048026 | positive regulation of mRNA splicing, via spliceosome |
| Biological Process | GO:0032968 | positive regulation of transcription elongation by RNA polymerase II |
| Biological Process | GO:0031053 | primary miRNA processing |
| Biological Process | GO:0050684 | regulation of mRNA processing |
| Biological Process | GO:0006446 | regulation of translational initiation |
| Biological Process | GO:0035194 | regulatory ncRNA-mediated post-transcriptional gene silencing |
| Biological Process | GO:0006401 | RNA catabolic process |
| Biological Process | GO:0008380 | RNA splicing |
| Biological Process | GO:0006408 | snRNA export from nucleus |
| Biological Process | GO:0000245 | spliceosomal complex assembly |
Reference
[1] Yang D, Yin J, Shan L, Yi X, Zhang W et al.. Identification of lysine-lactylated substrates in gastric cancer cells.. iScience 25(7):104630. 2022 Jul 15. PMID: 35800753.
[2] Yang Z, Yan C, Ma J, Peng P, Ren X et al.. Lactylome analysis suggests lactylation-dependent mechanisms of metabolic adaptation in hepatocellular carcinoma.. Nat Metab 5(1):61-79. 2023 Jan. PMID: 36593272.
[3] He C, Zhang J, Bai X, Lu C, Zhang K. Lysine lactylation-based insight to understanding the characterization of cervical cancer.. Biochim Biophys Acta Mol Basis Dis 1870(7):167356. 2024 Oct. PMID: 39025375.
[4] He J, Lai T, Zhou Z, Yang H, Lei Z et al.. Multiomics profiling reveals the involvement of protein lactylation in nonhomologous end joining pathway conferring radioresistance in lung adenocarcinoma cell.. Sci Rep 15(1):24651. 2025 Jul 9. PMID: 40634431.
[5] Wu Q, Li Z, Gong T, Zheng X, Zhou X et al.. Porphyromonas gingivalis infection induces lysine lactylation reprogramming in human umbilical vein endothelial cells.. Front Cell Infect Microbiol 16:1706727. 2026. PMID: 41696360.