Pauw P G, David J D
Division of Biological Sciences, University of Missouri, Columbia 65211.
Exp Cell Res. 1990 Jan;186(1):74-82. doi: 10.1016/0014-4827(90)90212-s.
We have previously identified several developmentally regulated surface polypeptides in the L6 rat myoblast cell line, on the basis of their susceptibility to lactoperoxidase catalyzed iodination. An analysis of the turnover rates of these polypeptides now indicates that while the bulk of the iodinated polypeptides have a half-life of 20-30 h, four low-molecular-weight polypeptides have half lives of 2-7 h. The half-lives of all of the rapid turnover class surface polypeptides were greatly increased in cultures where fusion was inhibited by chloroquine and in nonfusing variants of the L6 cell line. In contrast, inhibition of fusion by the metalloendoprotease inhibitor 1, 10-phenanthroline did not alter the turnover of any iodinatable surface proteins. We propose that some or all of the rapid turnover class of polypeptides may be surface receptors which control cell surface alterations involved in the acquisition of fusion competence or in fusion itself.
我们之前已在L6大鼠成肌细胞系中鉴定出几种受发育调控的表面多肽，这是基于它们对乳过氧化物酶催化碘化反应的敏感性。对这些多肽周转率的分析表明，虽然大部分碘化多肽的半衰期为20 - 30小时，但有四种低分子量多肽的半衰期为2 - 7小时。在融合被氯喹抑制的培养物以及L6细胞系的非融合变体中，所有快速周转类表面多肽的半衰期都大大延长。相比之下，金属内蛋白酶抑制剂1,10 - 菲咯啉对融合的抑制并未改变任何可碘化表面蛋白的周转率。我们提出，部分或所有快速周转类多肽可能是表面受体，它们控制着与获得融合能力或融合本身相关的细胞表面变化。
