Data from: Paternal epigenetic effects of population density on locust phase-related characteristics associated with heat-shock protein expression

Many species exhibit transgenerational plasticity by which environmental cues experienced by either parent can be transmitted to their offspring, resulting in phenotypic variants in offspring to match ancestral environments. However, the manner by which paternal experiences affect offspring plasticity through epigenetic inheritance in animals generally remains unclear. In this study, we examined the transgenerational effects of population density on phase-related traits in the migratory locust Locusta migratoria. Using an experimental design that explicitly controls genetic background, we found that the effects of crowd or isolation rearing on phase plasticity could be inherited to the offspring. The isolation of gregarious locusts resulted in reduced weight in offspring eggs and altered morphometric traits in hatchlings, whereas crowding of solitarious locusts exhibited opposite effects. The consequences of density changes were transmitted by both maternal and paternal inheritance, although the expression of paternal effects was not as pronounced as that of maternal effects. Prominent expression of heat-shock proteins (Hsps), such as Hsp90, Hsp70, and Hsp20.6, could be triggered by density changes. Hsps were significantly upregulated upon crowding but downregulated upon isolation. The variation in parental Hsp expression was also transmitted to the offspring, in which the pattern of inheritance was consistent with that of phase characteristics. These results revealed a paternal effect on phase polyphenism and Hsp expression induced by population density, and defined a model system that could be used to study the paternal epigenetic inheritance of environmental changes.

诸多物种均表现出跨代可塑性（transgenerational plasticity）：亲本一方所经历的环境信号可传递至子代，使子代产生表型变异以匹配祖先所处的环境。然而，在动物中，父本经历如何通过表观遗传影响子代可塑性的具体机制，目前仍未明确。本研究以飞蝗（Locusta migratoria）为研究对象，探究了种群密度对其相型相关性状的跨代影响，并采用严格控制遗传背景的实验设计，结果发现：群居或隔离饲养对飞蝗相型可塑性的影响可传递至子代。将群居型飞蝗进行隔离饲养，会导致其子代卵的重量降低，且初孵若虫的形态学性状发生改变；而对散居型飞蝗进行群居饲养，则会产生相反的效应。种群密度改变所产生的效应可通过母本遗传和父本遗传两种途径传递给子代，不过父本效应的表现强度不及母本效应显著。种群密度变化可诱导热休克蛋白（heat-shock proteins, Hsps）的显著表达，涵盖Hsp90、Hsp70及Hsp20.6等亚型；其中群居饲养可显著上调Hsps的表达水平，而隔离饲养则会使其表达水平下调。亲本Hsp表达的变异同样可传递至子代，且其遗传模式与相型性状的遗传模式一致。本研究结果揭示了种群密度诱导的相型多态性及Hsp表达所受的父本调控效应，并构建了可用于探究环境变化引发的父本表观遗传的实验模型系统。