CELL PROTEIN DEGRADATION IN CULTURED RAT EMBRYO FIBROBLASTS - SUPPRESSION BY VINBLASTINE OF ENHANCED PROTEOLYSIS BY SERUM-DEFICIENT MEDIA
CELL PROTEIN DEGRADATION IN CULTURED RAT EMBRYO FIBROBLASTS - SUPPRESSION BY VINBLASTINE OF ENHANCED PROTEOLYSIS BY SERUM-DEFICIENT MEDIA
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DOI：
10.1016/0304-4165(76)90146-x
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发表时间：
1976-01-01
期刊：
影响因子：
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通讯作者：
SARGUS, MJ
中科院分区：
文献类型：
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作者：
AMENTA, JS;BACCINO, FM;SARGUS, MJ
用L-[14C]亮氨酸标记培养在含10%血清的鹰S最低必需培养液中的大鼠胚胎成纤维细胞。冷追逐24小时后，通过测量培养液中可溶于三氯乙酸的14C的出现来评估蛋白水解率。在含10%血清(基础)的最低基本培养液中，细胞的蛋白水解率为1%/h，而单独放置在最低基本培养液(血清缺乏)中的细胞，蛋白分解的刺激率为3-4%/h，这种促进的蛋白分解是短暂的，仅在细胞被放置在缺乏血清的培养液中后的头4~8 h发生。长春花碱10~(-5)M对促进的蛋白降解抑制40%，但对基础蛋白降解无影响。对照实验表明，没有检测到细胞外蛋白质的水解，长春花碱也没有影响蛋白质合成的速度。基础的和增强的蛋白分解在细胞中可能至少有部分不同的机制；只有增强的蛋白分解才可能涉及微管。
Rat embryo fibroblasts grown in Eagle''s minimal essential medium with 10% serum were labeled with L-[14C]leucine. After a 24 h cold chase, rates of proteolysis were evaluated by measuring the appearance of trichloroacetic acid-soluble 14C in the media. Cells remaining in minimal essential medium with 10% serum (basal) showed a proteolysis rate of 1% per h, whereas cells placed in minimal essential medium alone (serum-deficient) showed a stimulation of proteolysis of 3-4% per h. This enhanced proteolysis was transitory, occurring only for the 1st 4-8 h after cells were placed in the serum-deficient media. Vinblastine 10-5 M inhibited the enhanced proteolysis 40% but had no effect on basal proteolysis. Control experiments showed no detectable hydrolysis of extracellular proteins, nor did vinblastine affect the rate of protein synthesis. Basal and enhanced proteolysis may have at least partially distinct mechanisms in the cell; only enhanced proteolysis may involve microtubules.