Kalosaka Katerina, Soumaka Elisavet, Politis Nikos, Mintzas Anastassios C
Division of Genetics, Cell and Developmental Biology, Department of Biology, University of Patras, Patras, Greece.
J Insect Physiol. 2009 Jun;55(6):568-73. doi: 10.1016/j.jinsphys.2009.02.002.
The relationship between Hsp70 expression and thermotolerance has been well documented in Drosophila melanogaster. However, there is limited information on this relationship in other insect species. In this report we describe the Hsp70-thermotolerance relationship in one of the major fruit fly pests, Ceratitis capitata (medfly). Hsp70 expression and thermotolerance were assayed at a range of temperatures in several stages of medfly development. The most thermotolerant stage was found to be the late larval stage (100% survival at 41 degrees C) followed by adult flies and late embryos (100% survival at 39 degrees C). These three stages showed a positive relationship between Hsp70 expression and thermotolerance. Mid-larval and mid-embryonic stages were found less thermotolerant and the Hsp70-thermotolerance relationship was not evident. Early embryos did not express Hsp70 at any temperature and exhibited the lowest thermotolerance. The relationship between Hsp70 and inducible thermotolerance was also studied in late larvae. A pretreatment at 37-39 degrees C increased thermotolerance at higher temperatures by approximately 1 degrees C. In parallel, the pretreatment increased Hsp70 expression suggesting a close link between Hsp70 expression and inducible thermotolerance. The increased Hsp70 levels after pretreatment were found to be due to the increased levels of the hsp70 RNA.
热休克蛋白70（Hsp70）表达与耐热性之间的关系在黑腹果蝇中已有充分记载。然而，关于其他昆虫物种中这种关系的信息有限。在本报告中，我们描述了主要果蝇害虫之一——地中海实蝇（Ceratitis capitata）中Hsp70与耐热性的关系。在地中海实蝇发育的几个阶段，在一系列温度下测定了Hsp70表达和耐热性。发现最耐热的阶段是幼虫后期（41℃时100%存活），其次是成虫和胚胎后期（39℃时100%存活）。这三个阶段显示出Hsp70表达与耐热性之间呈正相关。幼虫中期和胚胎中期阶段耐热性较差，Hsp70与耐热性的关系不明显。早期胚胎在任何温度下都不表达Hsp70，且耐热性最低。还在幼虫后期研究了Hsp70与诱导耐热性之间的关系。在37 - 39℃进行预处理可使较高温度下的耐热性提高约1℃。同时，预处理增加了Hsp70表达，表明Hsp70表达与诱导耐热性之间存在密切联系。预处理后Hsp70水平的增加被发现是由于hsp70 RNA水平的增加。
