Description
Carboxy-terminal domain, RNA polymerase II, polypeptide A phosphatase 1, also known as CTDSP1, is a class 2C phosphatase with activity dependent on the conserved DxD motif. CTDSP1 preferentially catalyzes the dephosphorylation of 'Ser-5' within the tandem 7 residues repeats in the C-terminal domain (CTD) of the largest RNA polymerase II subunit POLR2A. Also it negatively regulates RNA polymerase II transcription, possibly by controlling the transition from initiation/capping to processive transcript elongation. Recombinant human CTDSP1 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques