Induced thermotolerance and associated expression of the heat-shock protein Hsp70 in adult Drosophila melanogaster
Induced thermotolerance and associated expression of the heat-shock protein Hsp70 in adult Drosophila melanogaster
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DOI：
10.1046/j.1365-2435.1998.00246.x
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发表时间：
1998-10-01
影响因子：
5.2
通讯作者：
Justesen, J
中科院分区：
文献类型：
--
作者：
Dahlgaard, J;Loeschcke, V;Justesen, J
1.当温度上升到显著高于正常水平时，可诱导的热休克蛋白被合成。这些蛋白质的功能作用在细胞水平上是众所周知的。今天，人们对热休克蛋白在整个生物体抵抗高温胁迫和其他环境胁迫方面的重要性越来越感兴趣。通过比较成年果蝇在39℃下存活85min的耐热性和37℃短期升温/热硬化55min诱导耐热性后不同时间(2、4、8、16、32和h)的HSP70水平，探讨了热休克蛋白HSP70与成年果蝇耐热性之间的功能关系。男性和女性的HSP70水平均在热硬化后2小时达到最高，并随着时间的延长而下降。最初的下降速度很快，但随着时间的延长而减弱。32h后，未硬化果蝇的HSP70水平接近正常水平。在整个过程中，男性的HSP70水平高于女性。两性在热硬化后的存活率均随时间的延长而增加，在8~32h时达到最佳值。此后，随着时间的延长，阻力降低。除16岁以后和H.5岁外，雌性的存活率普遍高于雄性。对Hsp70水平的数据进行回归分析表明，描述这些数据的模型不能解释生存数据。此外，与女性相比，男性HSP70水平较高并不与男性更高的存活率相关。然而，对Hsp70和存活率的配对测量的统计分析表明，在诱导热耐受后的每个时间段，Hsp70水平与存活率呈正相关。
1. Inducible heat-shock proteins are synthesized when temperatures are increased to levels substantially above normal. The functional role of these proteins is well known at the cellular level. Today increasing interest has been directed towards the importance of heat-shock proteins for resistance of whole organisms to high-temperature stress and other environmental stressors.2. Here the functional relationship between the heat-shock protein, Hsp70, and thermal resistance in adult Drosophila melanogaster was examined by comparing thermal resistance, i.e, survival at 39 degrees C for 85 min, and levels of Hsp70 at various times elapsed (2, 4, 8, 16, 32 and 64 h) after thermotolerance was induced by short-term accrimation/heat hardening at 37 degrees C for 55 min.3. Levels of Hsp70 in both males and females were highest 2 h after heat hardening and declined with longer times elapsed. The rate of decrease initially was very fast but diminished with increasing time. After 32 h the level of Hsp70 approached the level in flies that were not hardened. Levels of Hsp70 in males exceeded that of females during the entire period.4. Survival of both sexes increased with increasing time after heat hardening and reached an optimum between 8 and 32 h. Thereafter resistance decreased with longer times elapsed. Survival of females generally exceeded that of males except after 16 and 64 h.5. Regression analysis applied to the data on Hsp70 levels revealed that the model describing these data could not explain the data for survival. Also, higher levels of Hsp70 in males compared with females were not associated with greater survival in males. However, statistical analysis on paired measurements of Hsp70 and survival revealed a positive association between Hsp70 level and survival at each time elapsed after induction of thermotolerance.