Phospho-CDK9 (Thr186) Antibody

• 产品编号：CST-2549S      品牌：CST       原厂货号：2549S
• 产品分类：抗体 > 一抗 > 磷酸化抗体
• 应用分类：

描述：

Phospho-CDK9 (Thr186) Antibody 能够检测内源性苏氨酸（186位）磷酸化的CDK9蛋白。该抗体可以识别42kDa和丰度较低的55kDa亚型。该多克隆抗体是由合成的人源的针对CDK9蛋白苏氨酸（186位）的磷酸化肽段免疫动物，采用多肽亲和层析技术生产的。 P-TEFb是一个普通的转录因子，它通过磷酸化RNA 聚合酶 II (RNAP II)C-末端尾巴结构域(CTD)来调节转录延伸。P-TEFb复合体由一个催化亚基，CDK9及其周期蛋白伴侣(可能是cyclin T1, T2a, T2b 或者 K)组成(回顾1,2)。P-TEFb被HIV Tat蛋白招募，促进转录延伸，随后病毒基因组开始复制。因此抑制P-TEFb的功能可以作为潜在的HIV疗法。CDK9以两种异构体的形式存在，一种是高丰度的42 kDa的异构体，一种是较低丰度的55 kDa的异构体并含有一个羧基末端延伸(3)。基于二者在淋巴细胞激活中的差异性表达(4,5)和核内定位的不同(5)，两种异构体似乎有明显不同的作用。周期蛋白依赖性激酶(CDKs)的激活部分经由周期蛋白的结合与T-回路结构域中保守区苏氨酸的磷酸化。一种不明的核激酶介导的CDK9 186位苏氨酸磷酸化可能在P-TEFb激活和HIV转录调节中发挥重要作用(7)。CDK9在44位赖氨酸的乙酰化影响其磷酸化RNAPII CTD的能力(8)。

1. Rice, A.P. and Herrmann, C.H. (2003) Curr HIV Res 1, 395-404.
2. De Falco, G. and Giordano, A. Cancer Biol Ther 1, 342-7.
3. Shore, S.M. et al. (2003) Gene 307, 175-82.
4. Shore, S.M. et al. (2005) Gene 350, 51-8.
5. Liu, H. and Herrmann, C.H. (2005) J Cell Physiol 203, 251-60.
6. Chen, R. et al. (2004) J Biol Chem 279, 4153-60.
7. Ammosova, T. et al. (2005) Retrovirology 2, 47.
8. Fu, J. et al. (2007) Mol Cell Biol 27, 4641-51.

原厂资料：

Specificity / Sensitivity

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. 

Source / Purification

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. 

Background

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 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). 

1. Rice, A.P. and Herrmann, C.H. (2003) Curr HIV Res 1, 395-404.
2. De Falco, G. and Giordano, A. Cancer Biol Ther 1, 342-7.
3. Shore, S.M. et al. (2003) Gene 307, 175-82.
4. Shore, S.M. et al. (2005) Gene 350, 51-8.
5. Liu, H. and Herrmann, C.H. (2005) J Cell Physiol 203, 251-60.
6. Chen, R. et al. (2004) J Biol Chem 279, 4153-60.
7. Ammosova, T. et al. (2005) Retrovirology 2, 47.
8. Fu, J. et al. (2007) Mol Cell Biol 27, 4641-51.

注意事项：

Storage: 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