This antibody gives a positive signal in the following whole cell lysates:
HeLa (Human epithelial carcinoma cell line)
Jurkat (Human T cell lymphoblast-like cell line)
HEK 293 (Human embryonic kidney cell line)
Storage instructionsShipped at 4°C. Store at +4°C short term (1-2 weeks). Upon delivery aliquot. Store at -20°C or -80°C. Avoid freeze / thaw cycle.
The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.
Use a concentration of 1 µg/ml.
1/250. Detects a band of approximately 43 kDa (predicted molecular weight: 43 kDa).
FunctionMember of the cyclin-dependent kinase pair (CDK9/cyclin-T) complex, also called positive transcription elongation factor b (P-TEFb), which facilitates the transition from abortive to production elongation by phosphorylating the CTD (C-terminal domain) of the large subunit of RNA polymerase II (RNAP II), SUPT5H and RDBP. The CDK9/cyclin-K complex has also a kinase activity toward CTD of RNAP II and can substitute for P-TEFb in vitro.
Sequence similaritiesBelongs to the protein kinase superfamily. CMGC Ser/Thr protein kinase family. CDC2/CDKX subfamily. Contains 1 protein kinase domain.
ICC/IF image of ab39098 stained human HeLa cells. The cells were PFA fixed (10 min), permabilised in TBS-T (20 min) and incubated with the antibody (ab39098, 1µg/ml) for 1h at room temperature. 1%BSA / 10% normal serum / 0.3M glycine was used to quench autofluorescence and block non-specific protein-protein interactions. The secondary antibody (green) was Alexa Fluor® 488 goat anti-rabbit IgG (H+L) used at a 1/1000 dilution for 1h. Alexa Fluor® 594 WGA was used to label plasma membranes (red). DAPI was used to stain the cell nuclei (blue).
Western blot - Anti-Cdk9 antibody (ab39098)
Anti-Cdk9 antibody (ab39098) at 1/250 dilution + Xenopus laevis gastrula embryo extract (Stage12) at 0.5 µg
Secondary Goat Anti-rabbit IgG Alexa Fluor 680 at 1/10000 dilution