Brown M, Kiehn D
Proc Natl Acad Sci U S A. 1977 Jul;74(7):2874-8. doi: 10.1073/pnas.74.7.2874.
We have tested the effects of exogenous proteases on the growth of normal and transformed hamster fibroblasts in the classic culture assays for transformation. The results indicate that exogenous proteases act to decrease the serum requirement of normal cells but not nearly to the extent that occurs in the process of viral transformation. Proteases do not further decrease the serum requirement of transformed cells, nor do they affect the maximal saturation density or the plating efficiency in soft agar of either normal or transformed cells. Under conditions optimal for growth stimulation, proteases decrease the strength of cell-to-substrate adhesion but do not affect cellular morphology. In contrast to previous studies, experiments using highly purified trypsin and several different active-site inhibitors strongly suggest that the growth-stimulatory activity of trypsin is not directly related to the proteolytic activity of the molecule.
我们在经典的转化培养试验中测试了外源性蛋白酶对正常和转化的仓鼠成纤维细胞生长的影响。结果表明，外源性蛋白酶可降低正常细胞对血清的需求，但降低程度远不及病毒转化过程中发生的程度。蛋白酶不会进一步降低转化细胞对血清的需求，也不会影响正常或转化细胞在软琼脂中的最大饱和密度或接种效率。在促进生长的最佳条件下，蛋白酶会降低细胞与底物的黏附强度，但不影响细胞形态。与先前的研究相反，使用高度纯化的胰蛋白酶和几种不同的活性位点抑制剂进行的实验强烈表明，胰蛋白酶的生长刺激活性与该分子的蛋白水解活性没有直接关系。
