Phospho-Troponin I (Cardiac) (Ser23/24) Antibody检测仅在Ser23/24位点磷酸化的内源性心脏的Troponin I蛋白。该抗体不能与磷酸化的骨骼肌troponin I发生交叉反应。通过人工合成人源troponin I蛋白Ser23/24位点周围相应的多肽片段去免疫动物从而制备出多克隆抗体。通过蛋白A和多肽亲和层析纯化抗体。Troponin蛋白连同tropomyosin蛋白一起发挥作用,该蛋白作为一个分子开关,在细胞内Ca2+浓度变化的情况下调节肌肉收缩。Troponin蛋白有三个亚型组成:Ca2+结合亚基troponin C (TnC)、肌球蛋白结合亚基troponin T (TnT)和抑制亚基troponin I (TnI)(1)。在心脏的β-adrenergic刺激下,TnI (cardiac)的Ser23和Ser24位点是通过PKA 和PKC 磷酸化。这个磷酸化刺激TnC蛋白的调节区域的构象变化,减少TnI和TnC的联系,并且通过减少肌丝Ca2+敏感度从而减少TnC蛋白的Ca2+结合度(1-3)。
Phospho-Troponin I (Cardiac) (Ser23/24) Antibody detects endogenous levels of cardiac troponin I only when phosphorylated at Ser23/24.This antibody does not cross-react with phosphorylated skeletal muscle troponin I.
Source / Purification
Polyclonal antibodies are produced by immunizing animals with a synthetic phosphopeptide corresponding to residues surrounding Ser23/24 of human troponin I (cardiac). Antibodies are purified by protein A and peptide affinity chromatography.
Background
Troponin, working in conjunction with tropomyosin, functions as a molecular switch, regulating muscle contraction in response to changes in the intracellular Ca2+ concentration. Troponin consists of three subunits: the Ca2+-binding subunit troponin C (TnC), the tropomyosin-binding subunit troponin T (TnT), and the inhibitory subunit troponin I (TnI) (1). In response to β-adrenergic stimulation of the heart, Ser23 and Ser24 of TnI (cardiac) are phosphorylated by PKA and PKC. This phosphorylation stimulates a conformational change of the regulatory domain of TnC, reduces the association between TnI and TnC, and decreases myofilament Ca2+ sensitivity by reducing the Ca2+ binding affinity of TnC (1-3).