Liu W, Tan Q-Q, Zhu L, Li Y, Zhu F, Lei C-L, Wang X-P
Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei Province, China.
Insect Mol Biol. 2017 Oct;26(5):530-542. doi: 10.1111/imb.12316. Epub 2017 May 20.
Temperate insects have evolved diapause, a period of programmed developmental arrest during specific life stages, to survive unfavourable conditions. During the diapause preparation phase (DPP), diapause-destined individuals generally store large amounts of fat by regulating nutrition distribution for the energy requirement during diapause maintenance and postdiapause development. Although nutritional patterns during the DPP have been investigated at physiological and biochemical levels in many insects, it remains largely unknown how nutritional metabolism is regulated during the DPP at molecular levels. We used RNA sequencing to compare gene expression profiles of adult female cabbage beetles Colaphellus bowringi during the preoviposition phase (POP) and the DPP. Most differentially expressed genes were involved in specific metabolic pathways during the DPP. Genes related to lipid and carbohydrate metabolic pathways were clearly highly expressed during the DPP, whereas genes related to protein metabolic pathways were highly expressed during the POP. Hormone challenge and RNA interference experiments revealed that juvenile hormone via its nuclear receptor methoprene-tolerant mediated the expression of genes associated with nutritional metabolism during the DPP. This work not only sheds light on the mechanisms of diapause preparation, but also provides new insights into the molecular basis of environmental plasticity in insects.
温带昆虫已经进化出滞育现象，即在特定生命阶段的一段程序性发育停滞期，以在不利条件下生存。在滞育准备阶段（DPP），注定进入滞育的个体通常通过调节营养分配来储存大量脂肪，以满足滞育维持和滞育后发育期间的能量需求。尽管在许多昆虫中，已经在生理和生化水平上研究了DPP期间的营养模式，但在分子水平上，DPP期间营养代谢是如何调节的，在很大程度上仍然未知。我们使用RNA测序来比较成年雌性菜粉蝶在产卵前期（POP）和DPP期间的基因表达谱。大多数差异表达基因参与了DPP期间的特定代谢途径。与脂质和碳水化合物代谢途径相关的基因在DPP期间明显高表达，而与蛋白质代谢途径相关的基因在POP期间高表达。激素挑战和RNA干扰实验表明，保幼激素通过其核受体耐甲氧普烯介导了DPP期间与营养代谢相关基因的表达。这项工作不仅揭示了滞育准备的机制，还为昆虫环境可塑性的分子基础提供了新的见解。
