MULTIPLE KINASE ARREST POINTS IN THE G1-PHASE OF NONTRANSFORMED MAMMALIAN-CELLS ARE ABSENT IN TRANSFORMED-CELLS
MULTIPLE KINASE ARREST POINTS IN THE G1-PHASE OF NONTRANSFORMED MAMMALIAN-CELLS ARE ABSENT IN TRANSFORMED-CELLS
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DOI：
10.1073/pnas.89.18.8626
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发表时间：
1992-09-15
影响因子：
11.1
通讯作者：
BRADBURY, EM
中科院分区：
文献类型：
--
作者：
GADBOIS, DM;CRISSMAN, HA;BRADBURY, EM
我们已经表明，非转化的哺乳动物细胞逮捕时，在细胞周期的G1期的早期与极低浓度的非特异性激酶抑制剂staurosporine处理，而转化细胞继续通过细胞周期的进展。我们现在已经用其他四种激酶抑制剂治疗了正常或转化的人皮肤成纤维细胞。其中三种抑制剂具有高度特异性：KT 5720抑制cAMP依赖性蛋白激酶，KT 5823抑制cGMP依赖性蛋白激酶，KT 5926抑制肌球蛋白轻链激酶。第四种抑制剂K252 b对蛋白激酶C具有中等特异性，但也抑制刚才提到的三种激酶。我们已经发现，这些抑制剂可逆地阻止正常人皮肤成纤维细胞在不同的时间在G1期，但不影响转化细胞的细胞周期进程。G1期内的停搏次数可分为两类。两个抑制剂，KT 5926和K252 b，在早期的时间，即几乎等于4小时后，从G 0到G1的过渡。cAMP和cGMP依赖性蛋白激酶抑制剂KT 5720和KT 5823在G 0/G1边界后几乎等于6小时的较晚时间阻滞细胞。这些数据表明，有多种激酶介导的不同底物的磷酸化是必不可少的正常细胞的进展，但不是转化细胞，通过G1期。这些抑制剂为我们提供了一套生化探针，在正常细胞G1期进展过程中激酶功能的研究中应该是非常宝贵的。
We have shown that nontransformed mammalian cells arrest early in the G1 phase of the cell cycle when treated with exceedingly low concentrations of the nonspecific kinase inhibitor staurosporine, whereas transformed cells continue to progress through the cell cycle. We have now treated normal or transformed human skin fibroblasts with four other kinase inhibitors. Three of these inhibitors are highly specific: KT5720 inhibits cAMP-dependent protein kinase, KT5823 inhibits cGMP-dependent protein kinase, and KT5926 inhibits myosin light-chain kinase. The fourth inhibitor K252b has a moderate specificity for protein kinase C but also inhibits the three kinases just mentioned. We have found that these inhibitors reversibly arrest normal human skin fibroblasts at different times in the G1 phase but do not affect the cell cycle progression of transformed cells. The times of arrest within the G1 phase can be divided into two categories. Two of the inhibitors, KT5926 and K252b, act at an early time that is almost-equal-to 4 h after the transition from G0 to G1. The cAMP- and cGMP-dependent protein kinase inhibitors KT5720 and KT5823 arrest cells at a later time that is almost-equal-to 6 h after the G0/G1 boundary. These data indicate that there are multiple kinase-mediated phosphorylations of different substrates that are essential for the progression of normal cells, but not transformed cells, through the G1 phase. These inhibitors provide us with a set of biochemical probes that should be invaluable in the study of the function of kinases during G1 phase progression of normal cells.