miR-34调控家蚕黑化免疫的分子机理研究

家蚕是重要的经济昆虫，也是鳞翅目昆虫的模式物种。研究表明，黑化反应是一种重要的免疫反应，在鳞翅目昆虫抵御病原微生物过程中具有重要作用。目前，miRNA功能的研究涵盖了生命过程的多个方面，这充分说明miRNA调控功能的多样性。目前大多数针对家蚕黑化免疫研究的焦点主要集中在蛋白质编码基因上，而miRNA的发现为揭示转录后水平调控黑化免疫反应机制开辟了新的方向。在前期，开展家蚕miR-34功能研究的过程中，发现miR-34过表达会引起家蚕幼虫表皮黑化的现象，我们推测miR-34参与了家蚕黑化免疫反应的调控，但是有关调控机制尚不清楚，因此，有必要深入研究miR-34在家蚕黑化免疫调控中的机制。基于此，本项目拟利用多种技术手段对miR-34在调控黑化免疫方面进行深入研究，挖掘其靶标基因，理清其调控网络，明确其调控机理，为研究转录后水平调控黑化免疫提供新证据。

Melanization, an important defense response, plays a vital role in arthropod immunity. At present, miRNAs participate in many physiological processes in insects. But there is limited information of how miRNA regulates melanization which plays an essential role in innate immunity. In our previous study, we found that miR-34 regulates larval growth and wing morphogenesis by directly modulating ecdysone signaling and cuticle protein in Bombyx mori. Meanwhile，we found the larva turning black with abnormal pigmentation in miR-34 overexpression silkworms, but the related molecular mechanisms are still unclear. Based on the these, this project intends to study the molecular function of miR-34 in melanization cascades by adopting CRISPR/Cas9 genome editing, transgenic technology system and bioinformatics approaches. Our aim is to reveal the mechanisms of miR-34 regulation on melanization and the downstream gene networks. We hope our results are helpful for understanding the regulation mechanisms of noncoding RNA in melanization cascades.