Phospho-eEF2 (Thr56) Antibody

• 产品编号：CST-2331S      品牌：CST       原厂货号：2331S
• 产品分类：抗体 > 一抗 > 磷酸化抗体
• 应用分类：

描述：

Phospho-eEF2 (Thr56) Antibody检测仅在Thr56位点磷酸化的内源性eEF2蛋白水平。该抗体不与在其它位点磷酸化的eEF2蛋白发生交叉反应。通过人工合成人类eEF2蛋白Thr56位点周围序列相应的磷酸化片段去免疫动物从而制备多克隆抗体。通过蛋白A和多肽亲和层析纯化抗体。

真核生物起始延伸因子2 (eEF2)能够促进peptidyl-tRNA从核糖体的A位点转运到P位点。研究显示eEF2激酶可在eEF2蛋白苏氨酸56位点对其磷酸化从而抑制eEF2蛋白的活性(1-4)。eEF2激酶通常是钙离子和钙调蛋白依赖的(5,6)。eEF2激酶也能被响应升高的cAMP水平的PKA所激活(7-9)，而cAMP水平的变化通常是由于应激或饥饿相关条件引起的。众所周知，多种处理方法可通过增加细胞内Ca2+或cAMP水平从而增加eEF2的磷酸化，最终抑制多肽链延伸。非活性的磷酸化eEF2能够被磷酸酶转化成具有活性的非磷酸化形式，其中最有可能的磷酸酶是蛋白磷酸酶-2A (PP-2A)。胰岛素能够在广泛的细胞类型中激活蛋白质的合成，且它能诱导eEF2通过mTOR信号通路快速去磷酸化，同时，胰岛素可能涉及到PP-2A或eEF2 kinase活性的调节(10)。

1. Nairn, A.C. and Palfrey, H.C. (1987) J. Biol. Chem. 262, 17299-17303.
2. Ryazanov, A.G. et al. (1988) Nature 334, 170-173.
3. Carlberg, U. et al. (1990) Eur. J. Biochem. 191, 639-645.
4. Redpath, N.T. et al. (1993) Eur. J. Biochem. 213, 689-699.
5. Nairn, A.C. et al. (1985) Proc. Natl. Acad. Sci. USA 82, 7939-7943.
6. Palfrey, H.C. et al. (1987) J. Biol. Chem. 262, 9785-9792.
7. Redpath, N.T. and Proud, C.G. (1993) Biochem. J. 293, 31-34.
8. Diggle, T. et al. (1998) Biochem. J. 336, 525-529.
9. Hovland, R. et al. (1999) FEBS Lett. 444, 97-101.
10. Proud, C. (2000) Translational Control of Gene Expression. Cold Spring Harbor Laboratory Press, NY, 719-739.

原厂资料：

Specificity / Sensitivity

Phospho-eEF2 (Thr56) Antibody detects endogenous levels of eEF2 only when phosphorylated at Thr56. It does not recognize eEF2 phosphorylated at other sites.

Source / Purification

Polyclonal antibodies are produced by immunizing animals with a synthetic phosphopeptide corresponding to residues surrounding Thr56 of human eEF2. Antibodies are purified by protein A and peptide affinity chromatography.

Background

Eukaryotic elongation factor 2 (eEF2) catalyzes the translocation of peptidyl-tRNA from the A site to the P site on the ribosome. It has been shown that phosphorylation of eEF2 at threonine 56 by eEF2 kinase inhibits its activity (1-4). eEF2 kinase is normally dependent on Ca2+ ions and calmodulin (5,6). eEF2 kinase can also be activated by PKA in response to elevated cAMP levels (7-9), which are generally increased in stress- or starvation-related conditions. A variety of treatments known to raise intracellular Ca2+ or cAMP levels have been shown to result in increased phosphorylation of eEF2, and thus to inhibit peptide-chain elongation. The inactive phosphorylated eEF2 can be converted to its active nonphosphorylated form by a protein phosphatase, most likely a form of protein phosphatase-2A (PP-2A). Insulin, which activates protein synthesis in a wide range of cell types, induces rapid dephosphorylation of eEF2 through mTOR signaling and may involve modulation of the activity of the PP-2A or the eEF2 kinase or both (10).

1. Nairn, A.C. and Palfrey, H.C. (1987) J. Biol. Chem. 262, 17299-17303.
2. Ryazanov, A.G. et al. (1988) Nature 334, 170-173.
3. Carlberg, U. et al. (1990) Eur. J. Biochem. 191, 639-645.
4. Redpath, N.T. et al. (1993) Eur. J. Biochem. 213, 689-699.
5. Nairn, A.C. et al. (1985) Proc. Natl. Acad. Sci. USA 82, 7939-7943.
6. Palfrey, H.C. et al. (1987) J. Biol. Chem. 262, 9785-9792.
7. Redpath, N.T. and Proud, C.G. (1993) Biochem. J. 293, 31-34.
8. Diggle, T. et al. (1998) Biochem. J. 336, 525-529.
9. Hovland, R. et al. (1999) FEBS Lett. 444, 97-101.
10. Proud, C. (2000) Translational Control of Gene Expression. Cold Spring Harbor Laboratory Press, NY, 719-739.

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.