长链非编码RNA调控果蝇机械感受器发育的分子机制研究

The neural regulatory mechanism of the development of mechanoreceptor is very important for the survival of Drosophila. Long noncoding RNA (lncRNA) is a class of newly emerged regulatory molecules, which is enriched in the nervous system. However, seldom study about the regulation of the mechanoreceptor development by lncRNA was reported. Our preliminary study discovered a lncRNA, lnc3, which is highly expressed in Drosophila neural system. In Drosophila genome, lnc3 located the upstream of one mechanoreceptor development-related gene, Smr. Overexpressing lnc3 upregulates the expression of the downstream Smr, and the bristle number of the scutellum in lnc3 mutant is 1-2 more than wildtype fly. Thus, we hypothesize that lnc3 regulate Drosophila mechanoreceptor development through regulating the expression of Smr. In this project, we will generate lnc3 transgenic and Smr mutant strains by transgenic or CRISPR/Cas9 technology, examine their regulatory functions in the mechanoreceptor development, identify the molecular mechanism with CHIP、RIP、mutant rescue experiment、DNA and histone methylation assay and so on. By this study, we aim to gain insights into the mechanism underlying the development of Drosophila mechanoreceptor and enrich the biological functions of long noncoding RNA.

果蝇外周神经机械感受器发育的神经调控机制对果蝇的生存至关重要。长链非编码RNA在神经系统中具有丰富的表达，而对其调控外周神经系统发育的研究极为少数。我们前期工作发现在果蝇神经系统中高度表达的lncRNA， lnc3。在果蝇基因组中，lnc3位于与果蝇刚毛发育相关基因Smrter的上游，在S2细胞中过表达lnc3能上调Smrter的表达，且lnc3的缺失导致果蝇背部盾板刚毛比野生型多1-2个。因此，我们推测lnc3通过调节Smrter的表达参与调控果蝇外周神经系统的发育。本项目将采用转基因和CRISPR/Cas9技术分别构建lnc3的过表达品系和Smrter的突变品系，探讨它们在果蝇背板刚毛发育中的神经调控作用；利用CHIP、RIP、突变挽回实验、DNA和组蛋白甲基化分析等手段研究两者间的分子调控机理。通过此项目，我们将深入了解果蝇机械刺激感受器的发育机制，丰富lncRNA的生物学功能。

果蝇外周神经机械感受器发育的神经调控机制对果蝇的生存至关重要。长链非编码RNA在神经系统中具有丰富的表达，而对其调控外周神经系统发育的研究极为少数。该项目深入研究了长链非编码 RNA SMRG（即lnc3） 调控果蝇背部盾板机械感受器（刚毛）发育的分子机制。实验结果表明 lncRNA SMRG 缺失表现为果蝇盾板刚毛增多同时伴有神经前体基因 scute 表达上调，提示scute为lncRNA SMRG的靶基因。通过检索文献并建立相关突变品系检测其表型证实抑制子 E(spl)mβ为SMRG调控scute的介导分子。通过遗传互作以及分子层面的各个实验包括实时定量PCR、双荧光报告系统、RNA免疫沉淀及染色质免疫沉淀等表明 SMRG 通过将抑制子 E(spl)mβ募集于神经前体基因 scute 启动子区，拮抗神经前体基因 scute 的表达从而负性调控果蝇盾板刚毛的发育。该项目的完成有助于深入理解果蝇机械感受器发育的分子机制，进一步丰富了lncRNA的生物学功能。在该基金的资助下，获得了一定的科研成果（RNA Biology 2019； Bio-101 2019；生物化学与生物物理进展 2019）。