Vallee R B, Davis S E
Proc Natl Acad Sci U S A. 1983 Mar;80(5):1342-6. doi: 10.1073/pnas.80.5.1342.
Microtubule-associated protein 1 (MAP 1; Mr = 350,000) was analyzed by column chromatography of microtubule protein obtained from calf brain gray and white matter. Two low molecular weight proteins (LMW MAPs; Mr 28,000 and 30,000) were found to cochromatograph with MAP 1 under all conditions examined. MAP 1 and the LMW MAPs were purified from calf brain white matter as a complex containing approximately equimolar amounts of the three species. Urea (6 M) was used to remove the LMW MAPs from MAP 1. Binding of MAP 1 to microtubules was unaffected by urea and occurred with or without the LMW species. Electron microscopy of microtubules composed of purified tubulin and either MAP 1 preparation revealed that, like MAP 2, MAP 1 has the appearance of a filamentous arm on the microtubule surface.
通过对从小牛脑灰质和白质中提取的微管蛋白进行柱层析分析微管相关蛋白1（MAP 1；分子量 = 350,000）。发现在所有检测条件下，两种低分子量蛋白（LMW MAPs；分子量28,000和30,000）与MAP 1共层析。MAP 1和LMW MAPs从小牛脑白质中作为一种复合物纯化出来，该复合物包含大约等摩尔量的这三种蛋白。使用6 M尿素从MAP 1上去除LMW MAPs。MAP 1与微管的结合不受尿素影响，无论有无低分子量蛋白均会发生。由纯化的微管蛋白和任何一种MAP 1制剂组成的微管的电子显微镜观察显示，与MAP 2一样，MAP 1在微管表面呈现出丝状臂的外观。
