Phospho-PKA C (Thr197) Antibody

• 产品编号：CST-4781S      品牌：CST       原厂货号：4781S
• 产品分类：抗体 > 一抗 > 磷酸化抗体
• 应用分类：

描述：

磷酸-PKA C（Thr197）抗体检测内源性的苏氨酸（197位）磷酸化的PKA C（-α-β-γ）蛋白。此抗体不与PKAÇ在其他磷酸化位点发生交叉反应。该多克隆抗体通过用合成磷酸肽免疫动物制备，该合成肽对应人PKA C苏氨酸（197位）附近的残基。抗体由protein A和肽亲和层析法纯化。在哺乳动物细胞中，第二信使环磷酸腺苷（cAMP）激活cAMP依赖性蛋白激酶（PKA或CAPK），并控制许多细胞机制，如基因转录，离子转运和蛋白磷酸化（1）。不活跃的PKA是异源四聚体，由一个二聚体调节亚基（R）和一个二聚体催化亚基（C）组成。当处于非活跃状态时，R亚基的假底物序列阻断C亚基上的活性位点。已经确定，有三种C亚基亚型（C-α，C-β，和C-γ）和两个调节亚基（RI，RII）家族，具有独特的与cAMP结合性能。两个R家族中存在的两种异构体，α和β（RI-α， RI-β，RII-α，RII-β）。cAMP与R亚基结合后，缓解自抑制接触作用，释放活跃的单体C亚基。PKA与Akt（PKB）和蛋白激酶C有底物特异性，其特点是-3位点的精氨酸与磷酸化丝氨酸或苏氨酸残基有关（2）。已经证明，具有这些共有序列的底物，会被PKA激酶磷酸化Bad (Ser155)、 CREB (Ser133)和 GSK-3 (GSK-3α Ser21和GSK-3β (Ser9)（3-5）等位点。此外，将PKAC-α和β同时下调，阻断了cAMP介导的Raf（Ser43和Ser259）的磷酸化（6）。自身磷酸化和通过PDK-1的磷酸化是两种已知的导致C亚基Thr197位点磷酸化的机制（7）。

1. Montminy, M. (1997) Annu. Rev. Biochem. 66, 807-822.
2. Dell'Acqua, M.L. and Scott, J.D. (1997) J. Biol. Chem. 272, 12881-12884.
3. Tan, Y. et al. (2000) J. Biol. Chem. 275, 25865-25869.
4. Gonzalez, G.A. and Montminy, M.R. (1989) Cell 59, 675-680.
5. Fang, X. et al. (2000) Proc. Natl. Acad. Sci. USA 97, 11960-11965.
6. Dumaz, N. and Marais, R. (2003) J. Biol. Chem. 278, 29819 -29823.
7. Moore, M.J. et al. (2002) J. Biol. Chem. 277, 47878-47884.

原厂资料：

Specificity / Sensitivity

Phospho-PKA C (Thr197) Antibody detects endogenous levels of PKA C (-alpha, -beta and -gamma) only when phosphorylated at Thr197. This antibody does not cross-react with PKA C phosphorylated at other sites.

Source / Purification

Polyclonal antibodies are produced by immunizing animals with a synthetic phosphopeptide corresponding to residues surrounding Thr197 of PKA C. Antibodies are purified by protein A and peptide affinity chromatography.

Background

The second messenger cyclic AMP (cAMP) activates cAMP-dependent protein kinase (PKA or cAPK) in mammalian cells and controls many cellular mechanisms such as gene transcription, ion transport, and protein phosphorylation (1). Inactive PKA is a heterotetramer composed of a regulatory subunit (R) dimer and a catalytic subunit (C) dimer. In this inactive state, the pseudosubstrate sequences on the R subunits block the active sites on the C subunits. Three C subunit isoforms (C-α, C-β, and C-γ) and two families of regulatory subunits (RI and RII) with distinct cAMP binding properties have been identified. The two R families exist in two isoforms, α and β (RI-α, RI-β, RII-α, and RII-β). Upon binding of cAMP to the R subunits, the autoinhibitory contact is eased and active monomeric C subunits are released. PKA shares substrate specificity with Akt (PKB) and PKC, which are characterized by an arginine at position -3 relative to the phosphorylated serine or threonine residue (2). Substrates that present this consensus sequence and have been shown to be phosphorylated by PKA are Bad (Ser155), CREB (Ser133), and GSK-3 (GSK-3α Ser21 and GSK-3β Ser9) (3-5). In addition, combined knock-down of PKA C-α and -β blocks cAMP-mediated phosphorylation of Raf (Ser43 and Ser259) (6). Autophosphorylation and phosphorylation by PDK-1 are two known mechanisms responsible for phosphorylation of the C subunit at Thr197 (7).

1. Montminy, M. (1997) Annu. Rev. Biochem. 66, 807-822.
2. Dell'Acqua, M.L. and Scott, J.D. (1997) J. Biol. Chem. 272, 12881-12884.
3. Tan, Y. et al. (2000) J. Biol. Chem. 275, 25865-25869.
4. Gonzalez, G.A. and Montminy, M.R. (1989) Cell 59, 675-680.
5. Fang, X. et al. (2000) Proc. Natl. Acad. Sci. USA 97, 11960-11965.
6. Dumaz, N. and Marais, R. (2003) J. Biol. Chem. 278, 29819 -29823.
7. Moore, M.J. et al. (2002) J. Biol. Chem. 277, 47878-47884.

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.