Effect of hyperthermia on nonhistone proteins isolated with DNA.
Effect of hyperthermia on nonhistone proteins isolated with DNA.
复制标题
高温对用 DNA 分离的非组蛋白的影响。
作者：
S. P. Tomasovic;G. Turner;W. Dewey
CHO细胞在45.5？C导致与DNA分离的非组蛋白蛋白增加。通过[3H]色氨酸与[C4C]胸苷的比值测量，该增加与加热持续时间成正比，加热15 min后为对照的1.5倍。X射线照射（高达3000拉德）对此结果没有影响。如果细胞培养在37？C加热后，回收率控制ratios发生在12 hr.Analysis标记的蛋白SDS平板凝胶电泳显示，热没有一致的密度或放射性差异，在个别nonhistone带。然而，加热确实在高分子量区域产生了非特异性的总体增加。这些结果与染色质分离技术（等渗与低渗）和培养条件（单层与悬浮液）无关。同样，当染色质从细胞或细胞核中分离时，也得到了类似的结果。这些结果将支持高温致死机制的假设，
Hyperthermic treatment of CHO cells at 45.5?C resulted in an increase in nonhistone protein isolated with DNA. The increase, as measured by [3H]tryptophan to [C4C]thymidine ratios, was proportional to heat duration and was 1.5 times the control after 15 min of heating. X irradiation (up to 3000 rad) had no effect on this result. If cells were incubated at 37?C after heating, recovery to control ratios occurred within 12 hr. Analysis of labeled protein by SDS slab gel electrophoresis showed that heat caused no consistent density or radioactivity differences in individual nonhistone bands. However, heat did produce a nonspecific overall increase in high molecular weight regions. These results were independent of the chromatin isolation technique (isotonic versus hypotonic) and of culturing conditions (monolayer versus suspension). Also, similar results were obtained when chromatin was isolated from either cells or nuclei. These results would support hypotheses for the mechanism of hyperthermic killing that invoke