水稻颖壳不仅可以保护内部花器官正常发育，还对糙米的生长具有重要影响，但目前关于颖壳极性发育的分子机制研究却十分匮乏。在本项目中，我们筛选到一个颖壳极性发育缺陷突变体dh3，颖壳退化变窄或形成芒状器官，DH3基因编码一个基因沉默抑制因子3，参与ta-siRNA的合成过程。本项目拟在此基础上，通过遗传学、细胞学、分子生物学、生物信息学、转录组学等手段，对DH3基因进行敲除和超表达分析、表达模式分析、蛋白定位分析、转录组分析、相关基因表达分析、cDNA文库构建和互作蛋白筛选与鉴定及小RNA测序分析，进一步研究DH3基因调控水稻颖壳发育的新功能，并深度解析DH3基因通过ta-siRNA合成途径调控颖壳极性发育的分子机制。研究结果对全面认识颖壳极性发育的分子机制和遗传调控网络，以及籽粒分子设计育种具有重要的理论和实践意义。

Glumes in rice not only protect the normal development of internal flower organs, but also have an important influence on the growth of brown rice. However, the current research on the molecular mechanism of the polarity development of glumes is very scarce. In this project, we identified a glume polarity developmental defect mutant dh3, which displayed narrowed or awn-like glumes. DH3 gene encodes a gene silencing suppressor 3, which is involved in the synthesis of ta-siRNA. Based on above results, the project intends to further study the function of DH3 gene by knockout and overexpression analysis, expression pattern analysis, protein localization analysis, transcriptome analysis, related gene expression analysis, cDNA library construction and interaction protein screening and identification, and small RNA sequencing analysis by means of genetics, cytology molecular biology, bioinformatics, and transcriptomics methods, to further study on the new function of DH3 gene regulating rice hull development, and deeply analyze the molecular mechanism of DH3 gene regulating the polarity development of glumes through ta-siRNA pathway. The research results have important theoretical and practical significance for comprehensive understanding of the molecular mechanism and genetic regulation network of glume polarity development and grain molecular design breeding.