CDK9 siRNA – Cyclin-Dependent Kinase 9 (Human)

The protein encoded by this gene is a member of the cyclin-dependent protein kinase (CDK) family. CDK family members are highly similar to the gene products of S. cerevisiae cdc28, and S. pombe cdc2, and known as important cell cycle regulators. This kinase was found to be a component of the multiprotein complex TAK/P-TEFb, which is an elongation factor for RNA polymerase II-directed transcription and functions by phosphorylating the C-terminal domain of the largest subunit of RNA polymerase II. This protein forms a complex with and is regulated by its regulatory subunit cyclin T or cyclin K. HIV-1 Tat protein was found to interact with this protein and cyclin T, which suggested a possible involvement of this protein in AIDS. [provided by RefSeq, Jul 2008]

CDK9: a protein kinase of the CDK family. Forms a complex with and is regulated by its regulatory subunit cyclin T or cyclin K. A component of the multiprotein complex TAK/P-TEFb, which is an elongation factor for RNA polymerase II-directed transcription and functions by phosphorylating the C-terminal domain of the largest subunit of RNA polymerase II. Transcriptional elongation factor and cofactor for HIV Tat protein; RNAi blocks HIV replication, and inhibitors also block varicella zoster replication. Mediates signals leading to cardiac hypertrophy. Inhibitor: Flavopiridol.

Protein type: Cell cycle regulation; Protein kinase, Ser/Thr (non-receptor); Kinase, protein; EC 2.7.11.22; Protein kinase, CMGC; Nuclear receptor co-regulator; EC 2.7.11.23; CMGC group; CDK family; CDK9 subfamily; CDK/CDK9 subfamily

Chromosomal Location of Human Ortholog: 9q34.1

Cellular Component: nucleoplasm; transcription elongation factor complex; PML body; transcription elongation factor complex b; intracellular membrane-bound organelle; membrane; cytoplasm

Molecular Function: RNA polymerase subunit kinase activity; protein binding; snRNA binding; DNA binding; cyclin-dependent protein kinase activity; chromatin binding; ATP binding; protein kinase activity

Biological Process: regulation of histone modification; transcription from RNA polymerase II promoter; transcription initiation from RNA polymerase II promoter; transcription, DNA-dependent; positive regulation of histone phosphorylation; viral reproduction; positive regulation of viral transcription; regulation of mitotic cell cycle; DNA repair; protein amino acid phosphorylation; regulation of DNA repair; cell proliferation; transforming growth factor beta receptor signaling pathway; RNA elongation from RNA polymerase II promoter; gene expression; replication fork arrest; positive regulation of transcription from RNA polymerase II promoter