microRNAs (miRNAs)是一类长约22个碱基的非编码小RNA。越来越多的研究表明miRNA在动植物体内广泛存在并对其生长发育有着重要调控作用。miR-318是一个在果蝇卵巢中高表达的miRNA,其缺失突变会引起雌性果蝇不育。进一步的研究表明miR-318缺失造成果蝇卵巢发育的异常，包括卵室发育过程中基因扩增和模式形成的缺陷。我们将利用传统遗传学，细胞生物学方法以及激光共聚焦显微镜，实时荧光定量PCR和微阵列表达谱技术，结合生物信息学，深入研究miR-318的功能，并且通过其靶基因的鉴定和功能分析构建一个基于miR-318的基因调控网络。我们对于miR-318功能的研究将阐明正常生理条件下以miRNA为核心的基因表达调控的机理，也能加深对于疾病发生发展尤其是雌性不育的分子机理的理解。

microRNAs (miRNAs) are a class of small noncoding RNAs, about 22 nucleotides in length. miRNAs have been found in both animals and plants,and they play important regulatory roles during development. miR-318 is one of miRNAs highly expressed in Drosophila ovaries, and lacking of miR-318 leads to low fertility in the female adults. Further studies show that the development of the ovary is abnormal in the absence of miR-318, characterized by the defects in gene amplification and pattern formation during egg chamber maturation. We are using a combination of several methodologies, including fly genetics, cell biology, confocal microscopy,real time quantitative PCR, microarray analysis and bioinformatics, to investigate the functions of miR-318 in detail. Identification and characterization of the target genes will help us to build a model for miR-318 mediated gene regulatory network. Taken together,functional studies of miR-318 will not only demonstrate the molecular mechanisms of miRNA mediated gene expression under normal physiological condition, but also provide novel insights into the development of diseases such as female infertility .

microRNA是一类长约22个核苷酸的内源性非编码小RNA，参与了生长发育和多种生理功能的调控。在该项目中，我们主要研究了一个果蝇卵巢高表达的microRNA，miR-318,在卵巢上皮细胞发育中的生物学功能。miR-318缺失突变雌性果蝇不育并且产形态异常的卵。进一步研究表明miR-318缺失扰乱卵室背前侧滤泡细胞模式形成，从而导致卵背部附属器官异常。miR-318突变引起卵壳蛋白基因扩增受损并导致卵壳薄且易破裂。我们在S2细胞中证明miR-318可以通过Dacapo 3’UTR的结合位点调控Dacapo的水平，说明Dacapo是miR-318的潜在靶基因。我们的实验也表明蜕皮激素信号通路能调控miR-318的表达。最后，我们发现miR-318和转录抑制因子tkk69协同作用共同调控卵巢滤泡上皮细胞中内复制到特异性基因扩增的转换。因此，miR-318在果蝇卵巢发育中的多种功能阐明了microRNA在维持卵巢上皮细胞命运和促进发育转换中的重要作用。