Singh H, Jungalwala F B
Int J Neurosci. 1979;9(2):123-31. doi: 10.3109/00207457909147227.
The turnover of proteins of myelin of brain was followed after an intracerebral injections of [1-14C] leucine into adult rats and compared with the turnover of proteins of total brain homogenate, microsomal and supernatant fractions. The myelin proteins were separated into three major fractions, viz., the Wolfgram, proteolipid and basic proteins as fluorescamine derivatives by a new preparative sodium-dodecylsulfate-polyacrylamide slab gel electrophoresis method. The bands were visualized, without staining, by their fluoresence under UV light. The maximal incorporation into myelin proteins was about 11% of that in the microsomal proteins. The maximum amoount ofnto myelin proteins was about 11% of that in the microsomal proteins. The incorporation of the label in myelin proteins reached a moximum about six hr after the injection, while the microsomal and supernatant and myelin proteins declined at multiphasic rates with half-lives varying from three hours to several days. Individual myelin proteins also appeared to turn over at multiphasic rates, with half-lives of 5, 20 and 90-100 days for the Wolfgram proteins, 7 and 100-120 days for the proteolipid proteins and 5 and 80-110 days for the basic proteins.
向成年大鼠脑内注射[1-¹⁴C]亮氨酸后，追踪脑髓鞘蛋白的更新情况，并与全脑匀浆、微粒体和上清液组分的蛋白更新情况进行比较。采用一种新的制备性十二烷基硫酸钠-聚丙烯酰胺平板凝胶电泳方法，将髓鞘蛋白分离为三个主要组分，即作为荧光胺衍生物的沃尔夫拉姆蛋白、蛋白脂质蛋白和碱性蛋白。通过紫外光下的荧光，在不染色的情况下使条带可视化。髓鞘蛋白的最大掺入量约为微粒体蛋白的11%。髓鞘蛋白中标记物的掺入在注射后约6小时达到最大值，而微粒体、上清液和髓鞘蛋白以多相速率下降，半衰期从3小时到几天不等。各个髓鞘蛋白似乎也以多相速率更新，沃尔夫拉姆蛋白的半衰期为5天、20天和90 - 100天，蛋白脂质蛋白的半衰期为7天和100 - 120天，碱性蛋白的半衰期为5天和80 - 110天。
