The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)



Gene Review

CCNC  -  cyclin C

Homo sapiens

Synonyms: CycC, Cyclin-C, SRB11 homolog, hSRB11
Welcome! If you are familiar with the subject of this article, you can contribute to this open access knowledge base by deleting incorrect information, restructuring or completely rewriting any text. Read more.

Disease relevance of CCNC


Psychiatry related information on CCNC


High impact information on CCNC

  • Cyclin C/cdk3 promotes Rb-dependent G0 exit [7].
  • We have isolated a novel 87 kDa cyclin C-related protein (cyclin T) that interacts specifically with the transactivation domain of Tat [8].
  • Cyclin C and E mRNAs accumulate periodically through the cell cycle, peaking at different times in G1 [9].
  • The cdk8/cyclin C protein complex is also found in a number of mammalian Mediator-like protein complexes, which repress activated transcription independently of the CTD in vitro [10].
  • Furthermore, cyclin C could be detected in K35 immunoprecipitates prepared from HeLa cells, indicating that the two proteins form a complex also in vivo [11].

Biological context of CCNC

  • Single-strand conformational polymorphism analysis of the remaining CCNC allele from patients with a deletion of one allele established that there were no further mutations within the exons or the flanking intronic sequences [1].
  • This suggested that cyclin C might play a role in cell cycle control, but progress toward understanding the function of this cyclin has been hampered by the lack of information on a potential kinase partner [11].
  • These results suggest either that haploinsufficiency of the cyclin C protein is sufficient to promote tumorigenesis or that the important tumor suppressor gene is linked to the CCNC locus [1].
  • Here we show that a non-cdk8-associated cellular pool of cyclin C combines with cdk3 to stimulate pRb phosphorylation at S807/811 during the G0/G1 transition, and that this phosphorylation is required for cells to exit G0 efficiently [7].
  • Furthermore, regulation of cell adhesion appears to be a feature unique to cyclin C, but not other G1 cyclins, E and D3, and its regulatory function is independent of CDK8 kinase activity [12].

Anatomical context of CCNC

  • The present observations suggest different cellular functions of cyclin C in neurons and astrocytes in AD [6].
  • Further role of Vitamin D is envisaged in identifying cyclin C as an important target for Vitamin D in cell-cycle regulation.Vitamin D at physiological concentration has been found to protect cell proteins and membranes against oxidative stress by inhibiting the peroxidative attack on membrane lipids [13].

Associations of CCNC with chemical compounds


Physical interactions of CCNC

  • We have identified at least two distinct cyclin C/CDK8 containing complexes within the cell, a larger complex over 500 kD in size, that also contains the largest subunit of RNA polymerase II, and a smaller 170 kD species [16].
  • In an article published recently in Cell, Ren and Rollins investigate mechanisms controlling the G0/G1 transition in quiescent cells and identify new cyclin C/Cdk3 complexes as key regulators of cell cycle reentry in human cells [17].

Other interactions of CCNC

  • Metazoan cyclin C was originally isolated by virtue of its ability to rescue Saccharomyces cerevisiae cells deficient in G1 cyclin function [11].
  • Unlike cyclin Ds and cyclin E, also identified in this screen, cyclin C has not been found to have a cell-cycle role in metazoa [18].
  • To study the involvement of cyclins in cell-cycle progression, changes of mRNA levels for three G1 cyclins (cyclin C, D1 and E) and cyclin A were studied in a leukemia cell line, HEL cells, before and after incubation with 12-O-tetradecanoylphorbol-13-acetate (TPA) [19].

Analytical, diagnostic and therapeutic context of CCNC

  • Consistent with the viability studies, the elevated TUNEL signal is reversed in cyclin C mutants [20].
  • To characterize the molecular mechanisms, we analyzed 8.4 kb of the cyclin C promoter by using chromatin immunoprecipitation assays (ChIP) with antibodies against acetylated histone 4, VDR and its partner receptor, retinoid X receptor (RXR) [4].


  1. Molecular cloning and chromosomal localization of the human cyclin C (CCNC) and cyclin E (CCNE) genes: deletion of the CCNC gene in human tumors. Li, H., Lahti, J.M., Valentine, M., Saito, M., Reed, S.I., Look, A.T., Kidd, V.J. Genomics (1996) [Pubmed]
  2. Highly frequent allelic loss of chromosome 6q16-23 in osteosarcoma: Involvement of cyclin C in osteosarcoma. Ohata, N., Ito, S., Yoshida, A., Kunisada, T., Numoto, K., Jitsumori, Y., Kanzaki, H., Ozaki, T., Shimizu, K., Ouchida, M. Int. J. Mol. Med. (2006) [Pubmed]
  3. Expression and gene amplification of primary (A, B1, D1, D3, and E) and secondary (C and H) cyclins in colon adenocarcinomas and correlation with patient outcome. Bondi, J., Husdal, A., Bukholm, G., Nesland, J.M., Bakka, A., Bukholm, I.R. J. Clin. Pathol. (2005) [Pubmed]
  4. Regulation of the human cyclin C gene via multiple vitamin D3-responsive regions in its promoter. Sinkkonen, L., Malinen, M., Saavalainen, K., Väisänen, S., Carlberg, C. Nucleic Acids Res. (2005) [Pubmed]
  5. Hypoxia modulates cyclin and cytokine expression and inhibits peripheral mononuclear cell proliferation. Naldini, A., Carraro, F. J. Cell. Physiol. (1999) [Pubmed]
  6. Cyclin C expression is involved in the pathogenesis of Alzheimer's disease. Ueberham, U., Hessel, A., Arendt, T. Neurobiol. Aging (2003) [Pubmed]
  7. Cyclin C/cdk3 promotes Rb-dependent G0 exit. Ren, S., Rollins, B.J. Cell (2004) [Pubmed]
  8. A novel CDK9-associated C-type cyclin interacts directly with HIV-1 Tat and mediates its high-affinity, loop-specific binding to TAR RNA. Wei, P., Garber, M.E., Fang, S.M., Fischer, W.H., Jones, K.A. Cell (1998) [Pubmed]
  9. Isolation of three novel human cyclins by rescue of G1 cyclin (Cln) function in yeast. Lew, D.J., Dulić, V., Reed, S.I. Cell (1991) [Pubmed]
  10. TFIIH is negatively regulated by cdk8-containing mediator complexes. Akoulitchev, S., Chuikov, S., Reinberg, D. Nature (2000) [Pubmed]
  11. Identification of human cyclin-dependent kinase 8, a putative protein kinase partner for cyclin C. Tassan, J.P., Jaquenoud, M., Léopold, P., Schultz, S.J., Nigg, E.A. Proc. Natl. Acad. Sci. U.S.A. (1995) [Pubmed]
  12. Functional cooperation of cyclin C and c-Myc in mediating homotypic cell adhesion via very late antigen-4 activation and vascular cell adhesion molecule-1 induction. Liu, Z.J., Tanaka, Y., Mine, S., Morinobu, A., Yagita, H., Okumura, K., Taniguchi, T., Yamamura, H., Minami, Y. Blood (1998) [Pubmed]
  13. Vitamin D and genomic stability. Chatterjee, M. Mutat. Res. (2001) [Pubmed]
  14. Characterization of mediator complexes from HeLa cell nuclear extract. Wang, G., Cantin, G.T., Stevens, J.L., Berk, A.J. Mol. Cell. Biol. (2001) [Pubmed]
  15. Gene expression profiles of hepatoma cell line BEL-7402. Liu, L.X., Jiang, H.C., Liu, Z.H., Zhu, A.L., Zhou, J., Zhang, W.H., Wang, X.Q., Wu, M. Hepatogastroenterology (2003) [Pubmed]
  16. Cyclin C/CDK8 is a novel CTD kinase associated with RNA polymerase II. Rickert, P., Seghezzi, W., Shanahan, F., Cho, H., Lees, E. Oncogene (1996) [Pubmed]
  17. Cyclin C makes an entry into the cell cycle. Sage, J. Dev. Cell (2004) [Pubmed]
  18. The cyclin C/Cdk8 kinase. Leclerc, V., Léopold, P. Progress in cell cycle research. (1996) [Pubmed]
  19. Increment of the cyclin D1 mRNA level in TPA-treated three human myeloid leukemia cell lines: HEL, CMK and HL-60 cells. Akiyama, N., Sasaki, H., Katoh, O., Sato, T., Hirai, H., Yazaki, Y., Sugimura, T., Terada, M. Biochem. Biophys. Res. Commun. (1993) [Pubmed]
  20. Regulation of the oxidative stress response through Slt2p-dependent destruction of cyclin C in Saccharomyces cerevisiae. Krasley, E., Cooper, K.F., Mallory, M.J., Dunbrack, R., Strich, R. Genetics (2006) [Pubmed]
WikiGenes - Universities