Rosenberg R N, Vandeventer L, De Francesco L, Friedkin M E
Proc Natl Acad Sci U S A. 1971 Jul;68(7):1436-40. doi: 10.1073/pnas.68.7.1436.
The specific activity of mouse neuroblastoma choline-O-acetyltransferase (EC 2.3.1.6.) increased 5.7-fold when the rate of cell division was restricted (as compared to cells kept rapidly dividing for 9 days); the specific activity of mouse neuroblastoma thymidylate synthetase increased 2.4-fold when nondividing cells again entered the logarithmic phase of cell growth. The highest specific activities for choline-O-acetyltransferase and lowest specific activities for thymidylate synthetase were obtained from cultures where cell division was restricted; the opposite result was observed when the cells were growing rapidly. Thus, the regulation of these two enzymes is out of phase with respect to each other and is dependent on the rate of cell division. The inverse relationship for the regulation of these two enzymes is discussed in relation to the needs of mitotic versus differentiated neuroblastoma cells.
当细胞分裂速率受到限制时(与持续快速分裂9天的细胞相比),小鼠神经母细胞瘤胆碱 - O - 乙酰转移酶(EC 2.3.1.6.)的比活性增加了5.7倍;当非分裂细胞再次进入细胞生长的对数期时,小鼠神经母细胞瘤胸苷酸合成酶的比活性增加了2.4倍。胆碱 - O - 乙酰转移酶的最高比活性和胸苷酸合成酶的最低比活性来自细胞分裂受到限制的培养物;当细胞快速生长时观察到相反的结果。因此,这两种酶的调节彼此不同步,并且依赖于细胞分裂速率。结合有丝分裂的神经母细胞瘤细胞与分化的神经母细胞瘤细胞的需求,讨论了这两种酶调节的反比关系。