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. Note: This description may include information from UniProtKB.
Protein type: Nuclear receptor co-regulator; Protein kinase, Ser/Thr (non-receptor); EC 220.127.116.11; Protein kinase, CMGC; EC 18.104.22.168; Kinase, protein; CMGC group; CDK family; CDK9 subfamily; CDK/CDK9 subfamily
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; viral reproduction; transcription, DNA-dependent; positive regulation of viral transcription; 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
SS: The number of records in which this modification site was determined using site-specific methods. SS methods include amino acid sequencing, site-directed mutagenesis, modification site-specific antibodies, specific MS strategies, etc.