Synthetic phosphopeptide corresponding to residues surrounding Ser2/5 of the Rpb1 CTD heptapeptide. Species sequence homology: Hamster, S. cerevisiae
RNA polymerase II is a complex of 12 proteins that participates in transcription, mRNA processing, and transcription-coupled DNA repair (1,2). The largest subunit, Rpb1, contains a unique heptapeptide: Tyr1, Ser2, Pro3, Thr4, Ser5, Pro6, Ser7, which is repeated up to 52 times in the carboxy-terminal domain CTD) of Rpb1 (3). This CTD is phosphorylated by cyclin-dependent kinases (cdks), p44/42 MAPK, DNAPKcs, and c-Abl (4). DNA damage caused by UV-light, hydrogen peroxide, or cisplatin results in ubiquitination and proteasomal degradation of Rpb1 (1,3). The kinase inhibitor 5, 6-dichloro-1-b- D-ribofuranosylbenzimidazole prevents ubiquitination of Rpb1, suggesting that CTD phosphorylation is required for proteolysis (5). Applications: Suitable for use in Western Blot and Immunohistochemistry. Other applications not tested. Recommended Dilution: Western Blot: 1:1000 Immunohistochemistry (Paraffin): 1:25 (Citrate/TBST) Optimal dilutions to be determined by the researcher. Storage and Stability: May be stored at 4C for short-term only. For long-term storage, aliquot and store at -20C. Aliquots are stable for 12 months at -20C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.
