Department of Zoology, Stockholm University, Svante Arrheniusväg 18b, Stockholm, S-106 91, Sweden.
Evolution. 2021 Feb;75(2):490-500. doi: 10.1111/evo.14151. Epub 2020 Dec 27.
Developmental plasticity describes the capacity of individuals with the same genotype to induce permanent change in a phenotype depending on a specific external input. One well-studied example of adaptive developmental plasticity is the induction of facultative diapause in insects. Studies investigating the inheritance of diapause induction have suggested diverse genetic origins. However, only few studies have performed genome-wide scans to identify genes affecting the induction decision. Here we compare two populations of the butterfly Pieris napi that differ in the propensity to enter diapause, and despite showing a low genome-wide divergence, we identify a few genomic regions that show high divergence between populations. We then identified a single genomic region associated with diapause induction by genotyping diapausing and directly developing siblings from backcrosses of these populations. This region is located on the Z chromosome and contained three circadian clock genes, cycle, clock, and period. Additionally, period harbored the largest number of SNPs showing complete fixation between populations. We conclude that the heritable basis of between-population variation in the plasticity that determines diapause induction resides on the Z chromosome, with the period gene being the prime candidate for the genetic basis of adaptive plasticity.
发育可塑性描述了具有相同基因型的个体根据特定的外部输入诱导表型发生永久变化的能力。适应性发育可塑性的一个很好的研究例子是昆虫的兼性休眠的诱导。研究诱导休眠的遗传的研究表明，存在不同的遗传起源。然而，只有少数研究进行了全基因组扫描来识别影响诱导决策的基因。在这里，我们比较了两个不同的 Pieris napi 蝴蝶种群，它们在进入休眠的倾向方面存在差异，尽管表现出低的全基因组分歧，但我们发现了一些种群之间存在高度分歧的基因组区域。然后，我们通过对这些种群的回交后代中的休眠和直接发育的同窝进行基因分型，鉴定出一个与休眠诱导相关的单一基因组区域。该区域位于 Z 染色体上，包含三个生物钟基因 cycle、clock 和 period。此外，period 基因中存在数量最多的 SNP，在种群之间完全固定。我们的结论是，决定休眠诱导的可塑性的种群间变异的可遗传性基础位于 Z 染色体上，period 基因是适应性可塑性遗传基础的主要候选基因。
