Calissano P, Cozzari C
Proc Natl Acad Sci U S A. 1974 May;71(5):2131-5. doi: 10.1073/pnas.71.5.2131.
Addition of nerve growth factor to a 105,000 x g supernatant of mouse brain induces the formation of a precipitate whose main constituent is the microtubule protein(s) (tubulin). The binding of nerve growth factor to purified tubulin is not inhibited by colchicine and does not appear to depend on the presence of GTP or Mg(++). GTP, however, and divalent cations, exert a marked effect on the increased turbidity induced by interaction of nerve growth factor with tubulin. These findings are tentatively interpreted with the hypothesis that binding of the factor to tubulin and the induced aggregation is a sequential two-step process; the latter but not the former would be influenced by GTP or divalent cations.
向小鼠脑105,000×g上清液中添加神经生长因子会诱导形成一种沉淀物,其主要成分是微管蛋白(微管素)。秋水仙碱不会抑制神经生长因子与纯化微管素的结合,而且这种结合似乎不依赖于鸟苷三磷酸(GTP)或镁离子(Mg++)的存在。然而,GTP和二价阳离子对神经生长因子与微管素相互作用所诱导的浊度增加有显著影响。这些发现初步解释如下:该因子与微管素的结合以及所诱导的聚集是一个连续的两步过程;后者而非前者会受到GTP或二价阳离子的影响。