Kampinga H H, Brunsting J F, Stege G J, Konings A W, Landry J
Department of Radiobiology, University of Groningen, The Netherlands.
Biochem Biophys Res Commun. 1994 Nov 15;204(3):1170-7. doi: 10.1006/bbrc.1994.2586.
Protein denaturation/aggregation upon cell exposure to heat shock is a likely cause of cell death. In the nucleus, protein aggregation has often been correlated to inhibition of nuclear located processes and heat-induced cell killing. In Chinese hamster O23 cells made thermotolerant by a prior heating (20'44 degrees C + 10h 37 degrees C) which induces the whole spectrum of heat shock proteins (hsps), the extent of nuclear protein aggregation during heat shock is reduced and the rate of recovery from aggregation after heat shock is enhanced. In contrast, a heat resistant Chinese hamster cell line overexpressing only hsp27 shows an unaltered sensitivity to formation of nuclear protein aggregates by heat, but shows the same enhanced rate of recovery from nuclear protein aggregation as thermotolerant cells. This suggests that accelerated recovery of protein aggregation could be partly responsible for hsp27-mediated thermoprotection.
细胞暴露于热休克时蛋白质变性/聚集很可能是细胞死亡的原因。在细胞核中，蛋白质聚集常常与抑制细胞核内发生的过程以及热诱导的细胞杀伤相关。在用先前加热（20℃至44℃ + 10小时37℃）使中国仓鼠O23细胞产生耐热性的过程中，该加热诱导了整个热休克蛋白（hsps）谱，热休克期间核蛋白聚集的程度降低，热休克后聚集恢复的速率提高。相比之下，仅过表达hsp27的耐热中国仓鼠细胞系对热诱导核蛋白聚集体形成的敏感性未改变，但与耐热细胞一样，其从核蛋白聚集中恢复的速率也提高。这表明蛋白质聚集的加速恢复可能部分地负责hsp27介导的热保护作用。
