水稻外稃形态建成基因的遗传筛选及功能分析

项目名称： 水稻外稃形态建成基因的遗传筛选及功能分析

项目编号： No.31300987

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 生物科学

项目作者： 宋显伟

作者单位： 中国科学院遗传与发育生物学研究所

项目金额： 23万元

中文摘要： 颖壳是禾本科植物所特有的花器官，包括内稃和外稃。它们位于小花结构的外层，保护内部器官避免病虫等侵入，提供种子发育所需的营养，同时颖壳大小也是种子大小的决定因素之一，直接决定种子产量。目前有关颖壳形态建成的分子机制了解得十分有限。申请者前期工作鉴定了一个控制水稻外稃发育的温敏突变体osrdr6-1，该突变体在高温条件下外稃发育缺陷而低温下发育正常。在高温条件下，我们发现osrdr6-1中tasiRNA和phased siRNA积累减少，tasiRNA的靶位点ARF基因表达上升并造成外稃发育缺陷。本研究拟以osrdr6-1为材料进行EMS诱变，在高温条件下筛选表型完全或者部分恢复的抑制子(suppressor)，采用图位克隆结合基因组大规模测序技术，鉴定参与水稻外稃形态建成的抑制子基因，通过功能分析阐述其可能的作用机制，完善水稻外稃发育和对环境响应的调控网络,为保证作物高产和稳产提供理论指导。

中文关键词： 水稻颖壳；表观遗传；小分子RNA；；

英文摘要： Glume, including palea and lemma, is the unique structures found only in the Peaceae. As the outer floral organ, glume is responsible for protecting kernels and florets from pathogen and insect attack as well as supplying carbohydrates to developing seeds. Meanwhile, the palea and lemma are directly associated with grain yield, because the glume size is one of the determinants of the size of endosperm or grain. However, the molecular mechanism underlying the glume morphogenesis is limited. Previously, we identified a temperature sensitive rice mutant, osrdr6-1, which shows awn-like lemma at high temperature but normal at low temperature. We found that tasiRNAs and phased small RNAs were less accumulation in osrdr6-1 at high temperature. Accordingly, the expression levels of ARF genes, which harbor the targeted sites of tasiRNA, were decreased, thus lead to the lemma defect in osrdr6-1 at high temperature. In this proposal, we will perform suppressor screening of osrdr6-1 and look for mutants back to normal under high temperature. Candidate genes will be identified by map-base cloning combined with genome-wide sequencing. Further functional analysis will reveal the regulatory roles of the identified genes on rice lemma development and help us to understand how plant response to different temperature. Thus, the kn

英文关键词： rice glume；epigenetic；small RNAs；；