Lee Y J, Dewey W C
J Cell Physiol. 1987 Jul;132(1):41-8. doi: 10.1002/jcp.1041320106.
After sodium arsenite (100 microM) treatment, the synthesis of three major heat shock protein families (HSPs; Mr = 110,000, 87,000, and 70,000), as studied with one-dimensional gels, was enhanced twofold relative to that of unheated cells. The increase of unique HSPs, if studied with two-dimensional gels, would probably be much greater. In parallel, thermotolerance was observed as a 100,000-fold increase in survival from 10(-6) to 10(-1) after 4 hr at 43 degrees C, and as a thermotolerance ratio (TTR) of 2-3 at 10(-3) isosurvival for heating at 45.5 degrees C. Cycloheximide (CHM: 10 micrograms/ml) or puromycin (PUR: 100 micrograms/ml), which inhibited total protein synthesis and HSP synthesis by 95%, completely suppressed the development of thermotolerance when either drug was added after sodium arsenite treatment and removed prior to the subsequent heat treatment. Therefore, thermotolerance induced by arsenite treatment correlated with an increase in newly synthesized HSPs. However, with or without arsenite treatment, CHM or PUR added 2-6 hr before heating and left on during heating caused a 10,000-100,000-fold enhancement of survival when cells were heated at 43 degrees C for 4 hr, even though very little synthesis of heat shock proteins occurred. Moreover, these cells manifesting resistance to heating at 43 degrees C after CHM treatment were much different than those manifesting resistance to 43 degrees C after arsenite treatment. Arsenite-treated cells showed a great deal of thermotolerance (TTR of about 10) when they were heated at 45 degrees C after 5 hr of heating at 43 degrees C, compared with less thermotolerance (TTR of about 2) for the CHM-treated cells heated at 45 degrees C after 5 hr of heating at 43 degrees C. Therefore, there are two different phenomena. The first is thermotolerance after arsenite treatment (observed at 43 degrees C or 45.5 degrees C) that apparently requires synthesis of HSPs. The second is resistance to heat after CHM or PUR treatment before and during heating (observed at 43 degrees C with little resistance at 45.5 degrees C) that apparently does not require synthesis of HSPs. This phenomenon not requiring the synthesis of HSPs also was observed by the large increase in thermotolerance to 45 degrees C caused by heating at 43 degrees C, with or without CHM, after cells were incubated for 6 hr following arsenite pretreatment. For both phenomena, a model based on synthesis and redistribution of HSPs is presented.
用亚砷酸钠（100微摩尔）处理后，通过一维凝胶电泳研究发现，三个主要热休克蛋白家族（HSPs；分子量分别为110,000、87,000和70,000）的合成相对于未加热的细胞增强了两倍。如果用二维凝胶电泳研究，独特HSPs的增加可能会大得多。同时，观察到热耐受性，即在43℃处理4小时后，存活率从10^(-6)提高到10^(-1)，提高了100,000倍，并且在45.5℃加热时，在10^(-3)等存活率下的热耐受比（TTR）为2 - 3。环己酰亚胺（CHM：10微克/毫升）或嘌呤霉素（PUR：100微克/毫升）可抑制总蛋白合成和HSP合成达95%，当在亚砷酸钠处理后添加其中任何一种药物并在随后的热处理前去除时，可完全抑制热耐受性的发展。因此，亚砷酸钠处理诱导的热耐受性与新合成的HSPs增加相关。然而，无论是否进行亚砷酸钠处理，在加热前2 - 6小时添加CHM或PUR并在加热期间保持存在，当细胞在43℃加热4小时时，存活率可提高10,000 - 100,000倍，尽管热休克蛋白的合成很少。此外，CHM处理后表现出对43℃加热有抗性的细胞与亚砷酸钠处理后表现出对43℃加热有抗性的细胞有很大不同。与在43℃加热5小时后再在45℃加热的CHM处理细胞相比（其热耐受性较低，TTR约为2），亚砷酸钠处理的细胞在43℃加热5小时后再在45℃加热时表现出较高的热耐受性（TTR约为10）。因此，存在两种不同的现象。第一种是亚砷酸钠处理后的热耐受性（在43℃或45.5℃观察到），显然需要合成HSPs。第二种是在加热前和加热期间进行CHM或PUR处理后的耐热性（在43℃观察到，在45.5℃几乎没有抗性），显然不需要合成HSPs。在亚砷酸钠预处理后孵育6小时后，无论是否有CHM，通过在43℃加热导致对45℃的热耐受性大幅增加，也观察到了这种不需要合成HSPs的现象。对于这两种现象，都提出了一个基于HSPs合成和重新分布的模型。
