Response of protein coding genes and microRNAs to temperature changes in four insect species

Insects are the most abundant described living creatures in the world, and they play important roles in our global ecosystem. Climate change affects global biodiversity, and researchers in many fields are striving to better understand the impact of the climate crisis. One such endeavour is the study of temperature-dependent effects on insects. At present, we know little of how climate affects gene expression in insects of different sexes. Here, we took four species of fruit flies of the genus Drosophila (D. melanogaster, D. virilis, D. pseudoobscura, and D. erecta), and subjected the male and female flies of each species to three different temperatures to test their sex-specific gene expression responses. A total of 144 transcriptomic profiles of protein-coding genes and microRNAs were generated. We found that, at the same temperature, there were more male-biased than female-biased protein-coding genes and microRNAs in all four investigated drosophilid species. Interestingly, upon temperature changes, there were more differentially expressed protein-coding genes in females than in males in all four investigated species, while the microRNAs were highly species- and sex-specific. This study provides the first evidence that sex-biased protein-coding gene and microRNA expression responses to temperature change differ between insect species within the same genus, and demonstrates the complexity of sex-specific responses of insects to climate change.