School of Life Sciences, Simon F.S. Li Marine Science Laboratory, State Key Laboratory of Agrobiotechnology, Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Hong Kong, China.
University of Exeter, Exeter, UK.
BMC Biol. 2023 Sep 25;21(1):200. doi: 10.1186/s12915-023-01703-1.
Lepidoptera (butterflies and moths) is one of the most geographically widespread insect orders in the world, and its species play important and diverse ecological and applied roles. Climate change is one of the biggest challenges to biodiversity this century, and lepidopterans are vulnerable to climate change. Temperature-dependent gene expression differences are of relevance under the ongoing climate crisis. However, little is known about how climate affects gene expression in lepidopterans and the ecological consequences of this, particularly with respect to genes with biased expression in one of the sexes. The common yellow butterfly, Eurema hecabe (Family Pieridae), is one of the most geographically widespread lepidopterans that can be found in Asia, Africa, and Australia. Nevertheless, what temperature-dependent effects there may be and whether the effects differ between the sexes remain largely unexplored.
Here, we generated high-quality genomic resources for E. hecabe along with transcriptomes from eight developmental stages. Male and female butterflies were subjected to varying temperatures to assess sex-specific gene expression responses through mRNA and microRNA transcriptomics. We find that there are more temperature-dependent sex-biased genes in females than males, including genes that are involved in a range of biologically important functions, highlighting potential ecological impacts of increased temperatures. Further, by considering available butterfly data on sex-biased gene expression in a comparative genomic framework, we find that the pattern of sex-biased gene expression identified in E. hecabe is highly species-specific, rather than conserved across butterfly species, suggesting that sex-biased gene expression responses to climate change are complex in butterflies.
Our study lays the foundation for further understanding of differential responses to environmental stress in a widespread lepidopteran model and demonstrates the potential complexity of sex-specific responses of lepidopterans to climate change.
鳞翅目（蝴蝶和蛾类）是世界上地理分布最广泛的昆虫目之一，其物种在生态和应用方面发挥着重要而多样的作用。气候变化是本世纪生物多样性面临的最大挑战之一，鳞翅目昆虫易受气候变化的影响。与正在发生的气候危机相关的是，依赖于温度的基因表达差异具有重要意义。然而，人们对气候如何影响鳞翅目昆虫的基因表达以及这种影响的生态后果知之甚少，特别是在性别偏倚表达的基因方面。普通黄蝶（Pieridae 科）是分布最广的鳞翅目昆虫之一，在亚洲、非洲和澳大利亚都有发现。尽管如此，可能存在哪些依赖于温度的影响，以及这些影响在性别之间是否存在差异，在很大程度上仍未得到探索。
在这里，我们为 E. hecabe 生成了高质量的基因组资源，以及来自八个发育阶段的转录组。雄性和雌性蝴蝶被置于不同的温度下，通过 mRNA 和 microRNA 转录组学来评估性别特异性基因表达反应。我们发现，雌性中存在更多依赖于温度的性别偏倚基因，这些基因涉及一系列重要的生物学功能，突出了温度升高的潜在生态影响。此外，通过在比较基因组框架中考虑可用的蝴蝶性别偏倚基因表达数据，我们发现 E. hecabe 中鉴定的性别偏倚基因表达模式具有高度的物种特异性，而不是在蝴蝶物种中保守，这表明蝴蝶对气候变化的性别偏倚基因表达反应是复杂的。
我们的研究为进一步了解广泛鳞翅目模型对环境压力的差异反应奠定了基础，并证明了鳞翅目对气候变化的性别特异性反应的潜在复杂性。
