P-TEFb is a general transcription factor that regulates transcription elongation through phosphorylation of the C-terminal tail domain (CTD) of RNA polymerase II (RNAP II).
The P-TEFb complex composed of a catalytic subunit, CDK9, and its regulatory cyclin partner, which can be cyclin T1, T2a, T2b or K (reviewed in 1,2).
P-TEFb is recruited by the HIV Tat protein to allow transcriptional elongation, and subsequent replication of the viral genome.
Inhibition of P-TEFb function therefore has potential for HIV therapy.
CDK9 exists as two isoforms, an abundant 42kD isoform, and a less abundant 55kD isoform, which contains an amino-terminal extension (3).
The two forms likely have distinct purposes based on differential expression during lymphocyte activation (4,5) and on their localization within the nucleus (5).
Cyclin dependent kinases (CDKs) are activated in part by cyclin binding and by phosphorylation of a conserved threonine in the T-loop domain.
Phosphorylation of CDK9 at the T-loop Thr186 by an unidentified nuclear kinase may be important in P-TEFb activation (6) and regulation of HIV transcription (7).
Acetylation of CDK9 at Lys44 affects its ability to phosphorylate the RNAPII CTD (8).
Applications:Suitable for use in Western Blot.
Other applications not tested.
Recommended Dilution:Western Blot: 1:1000, incubate membrane with diluted antibody in 5% w/v BSA, 1X TBS, 0.1% Tween-20 at 4°C with gentle shaking, overnight.
Optimal dilutions to be determined by the researcher.
Storage and Stability:For long-term storage, aliquot and store at -20°C.
Aliquots are stable for at least 12 months at -20°C.
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.
仕様
Size：100ul
Host：rabbit
Source Antibody：human
Grade：Affinity Purified
Purity：Purified by peptide affinity chromatography.
Form：Supplied as a liquid in 10mM sodium HEPES, pH 7.5, 150mM sodium chloride, 0.1mg/ml BSA, 50% glycerol.
Specificity：Detects endogenous levels of human CDK9 only when phosphorylated at Thr186. The antibody recognizes both the 42kD isoform and the less abundant 55kD isoform. Species Crossreactivity: mouse, rat and monkey
Isotype：IgG
Calc Applications Abbrev：WB
Calc Crossreactivity：Hu Mk Mo Rt
Immunogen：Synthetic phosphopeptide corresponding to residues surrounding Thr186 of human CDK9.
