Active Recombinant Human POLR2A, CT Domain

The carboxy-terminal repeat domain (CTD) of the largest subunit of RNA Pol II contains tandem repeats of a heptapeptide sequence Tyr-Ser-Pro-Thr-Ser-Pro- Ser which is highly conserved among eukaryotic organisms. There are two forms of RNA Pol II in vivo, designated IIO, which is extensively phosphorylated at the CTD, and IIA, which is not phosphorylated. The IIA form preferentially enters the pre-initiation complex (PIC), whereas IIO is found in the elongating complex. The kinase activity of TFIIH can mediate CTD phosphorylation, although other kinases, including Cdc2, Ctk1, the Srb10-Srb11 kinase-cyclin pair, and PTEFb, have also been implicated in CTD phosphorylation. A phosphatase responsible for the dephosphorylation of the CTD has also been identified. CTD phosphatase activity is regulated by TFIIB and TFIIF. The CTD has also been implicated in pre-mRNA processing, most likely functioning as a platform for the recruitment and assembly of factors involved in premRNA processing. Recombinant CTD is isolated from an E. coli strain that carries the coding sequence of human RNA Pol II carboxyterminal domain under the control of a T7 promoter. CTD has been applied in in vitro transcription assays, splicing assays and protein-protein interaction assays. The purified recombinant protein is greater than 95% homogeneous and contains no detectable protease, DNase, and RNase activity.

• Supplier: Creative Biomart
• Product #: POLR2A-1149H