Cyclin K

Cyclin K
PDB rendering based on 2i53.
Available structures PDB Ortholog search: PDBe, RCSB List of PDB id codes 2I53​, 4CXA​, 4NST​, 4UN0​
Identifiers
Symbols	CCNK ; CPR4
External IDs	OMIM: 603544 HomoloGene: 14748 GeneCards: CCNK Gene
Gene ontology Molecular function • cyclin-dependent protein serine/threonine kinase activity • protein binding • RNA polymerase II carboxy-terminal domain kinase activity • protein kinase binding Cellular component • cyclin K-CDK12 complex • cyclin K-CDK13 complex • nucleus Biological process • regulation of cyclin-dependent protein serine/threonine kinase activity • in utero embryonic development • regulation of transcription, DNA-templated • transcription from RNA polymerase II promoter • protein phosphorylation • cellular response to DNA damage stimulus • mitotic nuclear division • negative regulation by host of viral genome replication • cell division • negative regulation of cell cycle arrest • positive regulation of phosphorylation of RNA polymerase II C-terminal domain serine 2 residues Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	8812	12454
Ensembl	ENSG00000090061	ENSMUSG00000021258
UniProt	O75909	O88874
RefSeq (mRNA)	NM_001099402	NM_009832
RefSeq (protein)	NP_001092872	NP_033962
Location (UCSC)	Chr 14: 99.48 – 99.54 Mb	Chr 12: 108.18 – 108.2 Mb
PubMed search

Cyclin-K is a protein that in humans is encoded by the CCNK gene.^[1][2][3]

Function

The protein encoded by this gene is a member of the transcription cyclin family. These cyclins may regulate transcription through their association with and activation of cyclin-dependent kinases (CDK) that phosphorylate the C-terminal domain (CTD) of the large subunit of RNA polymerase II. This gene product may play a dual role in regulating CDK and RNA polymerase II activities.^[3]

Interactions

Cyclin K has been shown to interact with CDK9.^[2] Cyclin K also interacts with HIV nef protein.^[4]

References

1. Edwards MC, Wong C, Elledge SJ (Jul 1998). "Human cyclin K, a novel RNA polymerase II-associated cyclin possessing both carboxy-terminal domain kinase and Cdk-activating kinase activity". Molecular and Cellular Biology 18 (7): 4291–300. PMC 109013. PMID 9632813.
2. Fu TJ, Peng J, Lee G, Price DH, Flores O (Dec 1999). "Cyclin K functions as a CDK9 regulatory subunit and participates in RNA polymerase II transcription". The Journal of Biological Chemistry 274 (49): 34527–30. doi:10.1074/jbc.274.49.34527. PMID 10574912.
3. "Entrez Gene: CCNK cyclin K".
4. Khan SZ, Mitra D (Jul 2011). "Cyclin K inhibits HIV-1 gene expression and replication by interfering with cyclin-dependent kinase 9 (CDK9)-cyclin T1 interaction in Nef-dependent manner". The Journal of Biological Chemistry 286 (26): 22943–22954. doi:10.1074/jbc.M110.201194. PMID 21555514.

Further reading

• Lin X, Taube R, Fujinaga K, Peterlin BM (May 2002). "P-TEFb containing cyclin K and Cdk9 can activate transcription via RNA". The Journal of Biological Chemistry 277 (19): 16873–8. doi:10.1074/jbc.M200117200. PMID 11884399.
• Mori T, Anazawa Y, Matsui K, Fukuda S, Nakamura Y, Arakawa H (2002). "Cyclin K as a direct transcriptional target of the p53 tumor suppressor". Neoplasia 4 (3): 268–74. doi:10.1038/sj/neo/7900235. PMC 1531701. PMID 11988847.
• Beausoleil SA, Jedrychowski M, Schwartz D, Elias JE, Villén J, Li J, Cohn MA, Cantley LC, Gygi SP (Aug 2004). "Large-scale characterization of HeLa cell nuclear phosphoproteins". Proceedings of the National Academy of Sciences of the United States of America 101 (33): 12130–5. doi:10.1073/pnas.0404720101. PMC 514446. PMID 15302935.
• Lim J, Hao T, Shaw C, Patel AJ, Szabó G, Rual JF, Fisk CJ, Li N, Smolyar A, Hill DE, Barabási AL, Vidal M, Zoghbi HY (May 2006). "A protein-protein interaction network for human inherited ataxias and disorders of Purkinje cell degeneration". Cell 125 (4): 801–14. doi:10.1016/j.cell.2006.03.032. PMID 16713569.
• Olsen JV, Blagoev B, Gnad F, Macek B, Kumar C, Mortensen P, Mann M (Nov 2006). "Global, in vivo, and site-specific phosphorylation dynamics in signaling networks". Cell 127 (3): 635–48. doi:10.1016/j.cell.2006.09.026. PMID 17081983.
• Baek K, Brown RS, Birrane G, Ladias JA (Feb 2007). "Crystal structure of human cyclin K, a positive regulator of cyclin-dependent kinase 9". Journal of Molecular Biology 366 (2): 563–73. doi:10.1016/j.jmb.2006.11.057. PMC 1852425. PMID 17169370.