Potassium inhibition of transforming protein P85gag-mos and reversal of the transformed phenotype in 6m2 cells.
Potassium inhibition of transforming protein P85gag-mos and reversal of the transformed phenotype in 6m2 cells.
复制标题
钾抑制转化蛋白 P85gag-mos 并逆转 6m2 细胞中的转化表型。
DOI：
10.1002/jcp.1041340316
复制
发表时间：
1988
影响因子：
5.6
通讯作者：
Becker,FF
中科院分区：
文献类型：
--
作者：
Lai,CN;Gallick,GE;Maxwell,SA;Brinkley,BR;Becker,FF
据报道，高浓度的K+（52-72 mM高渗KCl）可诱导6 m2细胞的逆转变，6 m2细胞是感染温度敏感性转化病毒的正常大鼠肾细胞（NRK）的克隆。当暴露于高K+时，在允许温度（33°C）下生长的6 m2细胞表现出正常形态和减少的软琼脂生长，这是在非允许温度（39°C）下生长的细胞的特征。在目前的研究中，通过扫描电子显微镜证实，细胞扁平化和表面微绒毛重排发生在暴露于高K+的6小时内，类似于温度变化至39°C的影响。暴露于K+导致P85 gag-mos-相关丝氨酸激酶活性在5分钟内抑制90%，随后该蛋白的合成减少高达75%。这些变化在推定的转化蛋白是类似的温度变化引起的，被认为是逆转的基础。K+对细胞微管系统和F-肌动蛋白电缆的影响比温度变化至39°C更慢。前者直到72小时后才达到NRK细胞中所见的细网，但后者仍然异常。对酶的影响可能是由磷酸化的改变介导的，但激酶失活诱导逆转的机制尚不清楚。
K+at high concentrations (52–72 mM hypertonic KCI) has been reported to induce reverse transformation in the 6m2 cell, which is a clone of normal rat kidney cells (NRK) infected with a temperature‐sensitive transformation virus. When exposed to high K+, 6m2 cells grown at the permissive temperature (33°C) exhibit normal morphology and reduced soft agar growth, characteristics of cells grown at nonpermissive temperature (39°C). In the current study, flattening of cells and rearrangement of surface microvilli were demonstrated by scanning electron microscopy to occur within 6 hr of exposure to high K+, similar to the effect of temperature shift to 39°C. Exposure to K+resulted in a 90% inhibition of P85gag‐mos‐associated serine kinase activity within 5 min, with a subsequent reduction of up to 75% of the synthesis of this protein. These alterations in the putative transforming protein were similar to those induced by temperature shift and were considered to be the basis for retrotransformation. The cell microtubular system and F‐actin cables were affected more slowly by K+than by a temperature shift to 39°C. The former did not achieve the fine reticulum network seen in NRK cells until 72 hr later, but the latter remained aberrant. The effect on the enzyme might be mediated by alteration in phosphorylation, but the mechanism by which kinase inactivation induces retrotransformation is not yet known.