摘要
G_0期细胞在10％血清培养液刺激后向S期行进的早期出现微丝解聚的变化.细胞松弛素B(CB)0.5mg·L~_(-1)使微丝发生部分解聚能加强血清对DNA合成的刺激作用.但随着CB剂量的加大,微丝解聚的加强,便逐步增强对DNA合成的抑制作用.发现用5,10mg·L^(-1)的CB短时间处理G_0期细胞可强烈刺激蛋白激酶C(PKC)活性,虽使微丝暂时完全解聚,但不影响向S期的过渡及DNA的合成.促癌剂TPA(12-tetradecanoyl phorbol-13-acetate)可刺激G_0期细胞PKC活性,并能促进血清对DNA合成的刺激作用,但小剂量CB和TPA促进DNA的合成均依赖于血清的存在。
Medium containing 10% calf serum (CS) added to serum-arrested cells causes stress fibers to disassemble (within lh after CS exposure). Expoure of quiescent cells to 0.5mg·L^(-1) cytochalasin B (CB) results in a partial depolymerization of F-actin and promotion of DNA synthesis. However, this stimulation is dependent on the presence of growth factors in medium. The addition of increasing dose of CB(1 or 5 mg·L^(-1)) to cells evidently depo-lymerizes the stress fibers and inhibits DNA sythesis.Of particular interest is the fact that treatment with high concentration (5 or 10 mg·L^(-1)) of CB for 2h,completely disrupts F-actin structure in quiescent cells,but it evidently stimulates the activity of protein kinase C(PKC) and does not interfere with the transition from G_0 to S phase and DNA synthesis by serum. 12-tetradecanoyl phorbol-13-acetate(TPA, 100 μg·L^(-1))induces elevation of PKC activity in quiescent cells and enhances the stimulation of DNA synthesis by serum. However, the stimulation of TPA on DNA synthesis is also dependent on the presence of growth facttors in medium.
出处
《北京师范大学学报（自然科学版）》
CAS
CSCD
1992年第1期87-92,共6页
Journal of Beijing Normal University(Natural Science)
基金
国家自然科学基金
关键词
微丝解聚
DNA
PKC活性
CB
depolymerization of microfilaments
activity of PKC
DNA synthesis
cytochalasin B
12-tetradecanoyl phorbol-13-acetate
