Friedkin M, Legg A, Rozengurt E
Proc Natl Acad Sci U S A. 1979 Aug;76(8):3909-12. doi: 10.1073/pnas.76.8.3909.
Colchicine and other antitubulin agents markedly enhanced the stimulation of DNA synthesis by combinations of various growth factors such as epidermal growth factor, insulin, fibroblast-derived growth factor, and vasopressin in serum-free cultures of several quiescent 3T3 mouse fibroblast cell lines. Enhancing effects were observed based on continuous incorporation of [3H]thymidine into DNA as well as by autoradiographic labeling of cell nuclei. The concentration of colchicine and podophyllotoxin required to produce half-maximal enhancement of DNA synthesis stimulated by epidermal growth factor and insulin was 25-50 nM. Lumicolchicine did not produce enhancing effects. The disassembly of microtubules resulting from the action of colchicine, Colcemid, and vinblastine did not inhibit the stimulation of DNA synthesis in quiescent Swiss 3T3 fibroblasts by fetal bovine serum. We conclude that the cytoplasmic microtubule network in 3T3 mouse fibroblasts does not exert a positive regulatory function in the initiation of DNA synthesis but rather can produce a constraint on the initial action of the peptide growth factors in serum-free media.
秋水仙碱和其他抗微管蛋白药物显著增强了多种生长因子（如表皮生长因子、胰岛素、成纤维细胞衍生生长因子和血管加压素）组合在几种静止的3T3小鼠成纤维细胞系无血清培养中对DNA合成的刺激作用。基于[3H]胸腺嘧啶持续掺入DNA以及细胞核的放射自显影标记观察到了增强效应。产生表皮生长因子和胰岛素刺激的DNA合成半最大增强所需的秋水仙碱和鬼臼毒素浓度为25 - 50 nM。光秋水仙碱未产生增强作用。秋水仙碱、秋水仙酰胺和长春碱作用导致的微管解聚并未抑制胎牛血清对静止的瑞士3T3成纤维细胞DNA合成的刺激。我们得出结论，3T3小鼠成纤维细胞中的细胞质微管网络在DNA合成起始中不发挥正调节功能，而是会对无血清培养基中肽生长因子的初始作用产生限制。
