Data from: Inbreeding interferes with the heat shock response

Inbreeding is typically detrimental to individual fitness, with negative effects being often exaggerated in stressful environments. However, the causal mechanisms underlying inbreeding depression in general and the often increased susceptibility to stress in particular are not well understood. We here test whether inbreeding interferes with the heat shock response, comprising an important component of the stress response which may therefore underscore sensitivity to stress. To this end we subjected the tropical butterfly Bicyclus anynana to a full-factorial design with three temperatures and three levels of inbreeding, and measured the expression of heat shock protein (HSP) 70 via qPCR. HSP70 expression increased after exposure to heat as compared to cold or control conditions. Most strikingly inbreeding strongly interfered with the heat shock response, with inbred individuals showing a very weak upregulation of HSP70 only. Our results thus indicate that, in our study organism, interference with the heat shock response may be one mechanism underlying reduced fitness of inbred individuals, especially when exposed to stressful conditions. However, these indications need to be corroborated using a broader range of different temperatures, genes, and taxa.近交通常会对个体适合度造成损害，且其负面影响在胁迫环境中往往更为显著。然而，目前学界对于近交衰退的一般性因果机制，以及其为何常使生物对胁迫的易感性升高的具体机制，仍未得到充分阐明。 本研究旨在探究近交是否会干扰热休克反应（heat shock response）——这是生物体胁迫响应的核心组成部分，或可成为解释生物胁迫敏感性升高的潜在机制。为此，我们以热带蝴蝶眼蝶（Bicyclus anynana）为实验对象，采用包含3个温度梯度与3个近交水平的全因子实验设计，并通过实时定量聚合酶链反应（qPCR）检测热休克蛋白70（heat shock protein 70，HSP70）的表达水平。 相较于低温处理组与对照组，热胁迫处理后HSP70的表达量显著升高。 最引人注目的是，近交强烈干扰了热休克反应：近交个体仅表现出极微弱的HSP70表达上调。 因此，本研究结果表明，在本次实验的模式生物中，热休克反应受到干扰或许是近交个体适合度降低的潜在机制之一，尤其当它们暴露于胁迫环境下时。 不过，上述结论仍需在更广泛的温度梯度、基因范围与生物类群中加以验证。