The enzyme appears to be distinct from other protein kinases. It brings about multiple phosphorylations of the unique C-terminal repeat domain of the largest subunit of eukaryotic DNA-directed RNA polymerase (EC 22.214.171.124). The enzyme does not phosphorylate casein, phosvitin or histone.
Lee, J.M. and Greenleaf, A.L. A protein kinase that phosphorylates the C-terminal repeat domain of the largest subunit of RNA polymerase II. Proc. Natl. Acad. Sci. USA86 (1989) 3624–3628. [PMID: 2657724]
[EC 126.96.36.199 created 1992 as EC 188.8.131.52, transferred 2005 to EC 184.108.40.206]