GST-tagged RNA polymerase II Carboxy -Terminal Domain

• Species: Human
• Expression: Host E.coli
• Tag: GST-tag
• Purity: 90%
• Molecular Weight: 68.1 kDa.
• Gene Accession Number: NM_000937.

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 (1). 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 elongation complex (2-3). The kinase activity of TFIIH can mediate CTD phosphorylation (4), although other kinases, including Cdc2 (5), Ctk1 (6), the Srb10-Srb11 kinase-cyclin pair (7), and P-TEFb (8), have also been implicated in CTD phosphorylation. A phosphatase responsible for the dephosphorylation of the CTD has also been identified (9). CTD phosphatase activity is regulated by TFIIB and TFIIF (10). 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 pre-mRNA processing (11).

Recombinant GST-CTD is isolated from an E. coli strain that carries the coding sequence of human RNA pol II carboxy-terminal domain under the control of a T7 promoter.

GST-CTD has been applied in protein-protein interactions assays.

The purified protein is greater than 95% homogeneous based on SDS-PAGE analysis.
1 unit equals 1 nanogram of purified protein. 100 units (ng) are sufficient for a protein-protein interaction assay.

variable in different lots
1x dilution buffer A: 20 mM Tris-Cl (pH 8.0), 20% Glycerol, 100 mM KCl, 1 mM DTT and 0.2 mM EDTA

References:
1. Lu, H., et al., (1991) Proc. Natl. Acad. Sci. USA 88, 10004-10008
2. Dahmus, M.E. (1994) Prog. Nucleic Acid Res. Mol. Biol. 48, 143-179
3. O’Brian, T., et al., (1994) Nature 370, 75-77
4. Feaver, W. J., et al.,(1991) Cell 67, 1223-1230
5. Cisek, L.J., et al., (1989) Nature 339, 679-684
6. Lee, J. M., et al., (1991) Gene Expr. 1, 149-167
7. Liao, S. M., et al., (1995) Nature 374, 193-196
8. Marshall, N. F., et. al., (1996) J. Biol. Chem. 271, 27176-27183
9. Chambers, R.S., et al., (1994) J. Biol. Chem. 269, 26243-26248
10. Chambers, R. S., et al., (1995) J. Biol. Chem. 270, 14962-14969
11. McCracken, S., et al., (1997) Nature 385, 357-361

DISCLAIMER

This products is recommended For RESEARCH USE ONLY and is Not qualified for Use in Diagnostic or Therapeutic Procedures.