理想株型基因IPA1新等位位点的挖掘与人工创制研究

水稻理想株型基因IPA1具有壮秆、大穗、增产作用，及参与氮高效、抗病协同调控功能。IPA1基因表达受microRNA以及启动子和上游的非编码基因区的严格调控。已报道的IPA1高表达等位型有三个，水稻育种中使用ipa1-2D较多，但在粳稻的背景下ipa1-2D的表型不明显，所以目前IPA1的基因应用遗传基础比较狭窄，还不能满足水稻育种的需求。因此，本项目在前期已完成了水稻粗秆种质资源的不同IPA1等位型及利用频率分析，并在发现新IPA1弱等位位点的基础上，开展以下研究：(1)基于CRISPR/Cas9基因编辑技术突变IPA1非编码区，突变创制一系列IPA1新等位基因和不同表型株系；(2)关联分析非编码区的转录调控IPA1的功能，明确非编码区元件调控IPA1的分子机制；(3)精细分析IPA1不同突变类型株系的农艺性状，获得新型可用的IPA1等位基因，为提高水稻产量提供新的基因资源与育种材料。

IPA1, the ideal plant architecture gene in rice, plays an important role in grain yield, nitrogen assimilation and disease resistance. IPA1 is strictly regulated by microRNA and upstream non-coding region. Three high expression alleles of IPA1 have been reported, among them the ipa1-2D is widely used in rice breeding, but the phenotype of ipa1-2D in the Japonica background shows no significant. The application of IPA1 to the rice breeding has a long way to go due to the narrow genetic basis of IPA1. To broaden the insight of the IPA1 genetics basis, we identified the different ipa1 alleles utilization frequency in the rice germplasm resources with strong culms, a new weak IPA1 allele was identified. Based on the exsiting research: (1) We plan to use CRISPR/Cas9 genome editing technology to mutate the non-coding region of IPA1 to generate new IPA1 alleles; (2) Association analysis of the function of IPA1 non-coding region and clarify the molecular mechanism of non-coding region elements; (3) Through analysis the agronomic traits of new IPA1 mutant lines and obtain new available IPA1 alleles, which would provide new gene resources and breeding materials for rice breeding.