谷子粳糯性相关的microRNA及其靶基因鉴定与功能分析

谷子是我国的特色作物。提高品质一直是谷子育种的主要目标，而胚乳粳糯性是构成食味品质的关键因素。国内在谷子突变体研究、杂优利用、功能基因组、基因组测序与注释、Waxy基因等位变异、胚乳形成期转录组测序等方面进行了相关研究，但未见有关灌浆期籽粒小RNA和降解组测序分析及其应用于品质育种的报道。本项目以糯质公谷68和非糯品种赤谷4号为材料，自抽穗第12d-42d检测GBSSI和SBE的活性变化，利用小RNA和降解组测序，筛选保守miRNA和新的特异miRNA，鉴定特异miRNA序列靶基因转录本；利用转录组-小RNA-降解组关联分析，整合差异表达mRNA-miRNA表达谱，分析不同比较组miRNA和靶基因GO、KEGG富集性和网络调控；用qRT-PCR验证显著差异表达miRNA靶基因；借助于靶基因克隆、表达载体构建和遗传转化，初步探明差异靶基因的功能，为谷子食味品质改良提供参考依据。

Foxtail millet is Chinese special crop. Increase quality is main objective of foxtail millet breeding, no-waxy and waxy endosperm are the key factors of eating quality in millet. Mutant study, heterosis utilization, functional genome, genome sequencing and comments, waxy gene allelic variation and transcriptome sequencing during endosperm formation were studied in foxtail millet, but not reported on grain small RNA sequencing and degradome analysis applied to millet quality breeding in grouting. In this project, Gonggu68 and Chigu4, which have significant difference in amylose content, will be used to detect GBSSI and SBE activity of immatured seeds from 12 to 42 days after head sprouting. Conserved miRNAs, new specific miRNAs, target gene transcripts of specific miRNA sequences will be identified by small RNA and degradome sequencing analysis. Expression profile of differentially expressed mRNA-miRNA will be integrated. GO, KEGG enrichment andnetwork regulation of miRNA and their targets will be analyzed by transcriptome-small RNA-degradome combined analysis in different comparison groups. Verify the differential expressed miRNA targets using fluorescence quantitative RT-PCR. Preliminary clear function of different targets by using gene clone, expression vector construction and genetic transformation, so as to provide reference for millet eating quality improvement.