Western blot analysis of extracts from various cell types, untreated or treated with λ phosphatase and calf intestinal phosphatase (CIP), using Phospho-CDK9 (Thr186) Antibody (upper) or CDK9 (C12F7) Rabbit mAb #2316 (lower).
|REACTIVITY||H M R Mk|
|MW (kDa)||42, 55|
Supplied in 10 mM sodium HEPES (pH 7.5), 150 mM NaCl, 100 µg/ml BSA and 50% glycerol. Store at –20°C. Do not aliquot the antibody.
For western blots, incubate membrane with diluted primary antibody in 5% w/v BSA, 1X TBS, 0.1% Tween® 20 at 4°C with gentle shaking, overnight.
NOTE: Please refer to primary antibody product webpage for recommended antibody dilution.
From sample preparation to detection, the reagents you need for your Western Blot are now in one convenient kit: #12957 Western Blotting Application Solutions Kit
NOTE: Prepare solutions with reverse osmosis deionized (RODI) or equivalent grade water.
Load 20 µl onto SDS-PAGE gel (10 cm x 10 cm).
NOTE: Volumes are for 10 cm x 10 cm (100 cm2) of membrane; for different sized membranes, adjust volumes accordingly.
* Avoid repeated exposure to skin.
posted June 2005
revised June 2020
Protocol Id: 10
Phospho-CDK9 (Thr186) Antibody detects endogenous levels of CDK9 only when phosphorylated at Thr186. The antibody recognizes both the 42 kDa isoform and the less abundant 55 kDa isoform.
Human, Mouse, Rat, Monkey
Polyclonal antibodies are produced by immunizing animals with a synthetic phosphopeptide corresponding to residues surrounding Thr186 of human CDK9. Antibodies are purified using peptide affinity chromatography.
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 is 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 42 kDa isoform, and a less abundant 55 kDa 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).
Explore pathways + proteins related to this product.
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