circRNA介导的光敏色素构型互转对小麦光温敏雄性不育调控分子机制初探

CircRNA are a class of non-coding RNAs which could be involved in many life activities via interaction with miRNA. CircRNA are miRNA sponges which could hinder miRNA from exerting negative regulatory functions and attenuate miRNA regulating their target genes. Our research team previously investigated the light-induced male sterility mechanism and found that circRNA may regulate pollen development by involving in red/far red light (R / FR) signals. However, the process of the R/FR signals regulating fertility and the roles of circRNA in this process remains unclear. Therefore, we intend to use wheat Photo-Thermosensitive Genic Male Sterile (PTGMS) Line BS366 which under R/FR dark-breaking treatment as materials to screen and clone candidate circRNAs using high-throughput sequencing and 5'RACE technique in this project. In addition, regulating role of circRNA on miRNAs and their target genes will be explored via biological information analysis, RNA pull-down, ChIP, mutants and transgenic technology to reveal the regulation pattern of circRNA in the fertility conversion of photoperiod sensitive male sterile wheat induced by transduction of red-light absorption (Pr) and far red-light absorption (Prf).

环状RNA是一类由mRNA前体经反向可变剪切而来的共价闭合且保守的单链转录本，可吸附结合miRNA，并阻止miRNA发挥负调控功能，从而减弱对靶基因的调控表达。课题组前期在光照诱导雄性不育机制研究中，初步发现circRNA可能通过参与红光/远红光（R/FR）信号调控花粉发育。但是R/FR信号是如何调控育性，及circRNA在此过程中的作用和调控方式尚未明晰。故本项目拟以小麦光温敏雄性不育系BS366雄蕊组织为材料，通过R/FR暗间断处理，利用高通量测序、5’RACE等技术筛选并克隆候选circRNA。并利用生物信息学技术、RNA pull down、ChIP、突变体及转基因等技术研究circRNA对miRNA及mRNA的调控作用，揭示circRNA在红光吸收型（Pr）和远红光吸收型（Prf）互转诱导的、光温敏雄性不育小麦育性转换中的调控模式,为进一步研究光敏雄性不育机理提供理论基础。

光周期/温敏核不育（P/TGMS）系对杂种小麦杂种优势的利用具有重要意义。目前发现环状RNA（circRNA）和长非编码RNA（lncRNA）参与植物花药的发育，但它们对P/TGMS系雄性不育性的影响尚不清楚。在本研究中，我们通过对不同光照条件下光温敏核不育（PTGMS）小麦BS366育性转换期花药进行高通量测序，研究光周期及温度处理下，lncRNA和circRNA的差异表达及其生物学功能。并对候选的非编码RNA进行了初步的功能分析。主要研究结果如下：.1、明确了不同光质条件下，不育系BS366花药败育特征，发现远红光暗间断对光温敏雄性不育小麦育性恢复有一定的调控作用。.2、发现茉莉酸信号通路中重要的受体蛋白MYC，可能通过参与JA-light crosstalk 通路，进而参与红光吸收型（Pr）和远红光吸收型（Prf）互转诱导的育性转换；.3、发现circRNA / lncRNA-mRNA-miRNA（ceRNA，内源竞争RNA）可能通过参与糖类代谢途径，进而调控花药发育。.4、克隆了其差异表达的lncRNA27195及其靶基因TaRTS，发现其与绒毡层提前降解及雄性不育密切关联。