激活素A(Activin A)是具有广泛生物学活性的TGF-β家族成员,其活性包括调节细胞增殖和分化,以及促进神经元存活。激活素A在患有结肠直肠肿瘤的人和绝经后妇女的体内含量升高,分别与大肠癌和乳腺癌的发生有关。激活素A的生物活性可以通过抑制素和由扩散型TGF-β拮抗剂(卵泡抑素)被中和。激活素A结合两种形式的I型受体(Act RI-A and Act RI-B) 和两种形式的II型受体(Act RII-A and Act RII-B)。激活素是同型二聚体或不同β亚基的异源二聚体。它们产生作为前体蛋白,该蛋白的氨基酸末端可被裂解,从而释放C-末端有生物活性的配体。人/小鼠/大鼠激活素A 26.0 kDa,是由二硫键连接两个βA链的同型二聚体,每条链含116个氨基酸残基。
原厂资料:
Activin A is a TGF-β family member that exhibits a wide range of biological activities including regulation of cellular proliferation and differentiation, and promotion of neuronal survival. Elevated levels of Activin A in human colorectal tumors and in postmenopausal women have been implicated in colorectal and breast cancers, respectively. The biological activities of Activin A can be neutralized by inhibins and by the diffusible TGF-β antagonist, follistatin. Human/Murine/Rat Activin A is a 26.0 kDa disulfide-linked homodimer of two βA chains, each containing 116 amino acid residues.