新株型基因NPT2增加水稻产量的分子机制研究

The stability and improvement of rice yield is related to the food security of our country and even the whole world. With the decrease of cultivated land, we continuously improve the total yield of rice only by increasing the yield per unit area. The improvement of plant type is one of the main directions of high-yield breeding in rice. The study of genetic network about establishment of rice plant type will provide a solid theoretical basis for breeding. In previous studies, we cloned NPT1 (New Plant Type 1) from ideal plant type rice in IRRI. Base on similar strategies, we identified a novel gene named NPT2, which simultaneously controlled rice plant type and yield. It was also found that NPT2 could interact with NPT1 protein. Based on that, this project focuses on the molecular mechanism of NPT2 regulating plant type. Downstream target genes regulated by NPT2, NPT1 and OsSPL14 will be analyzed by RNA-seq. The biological significance of the interaction of NPT2, NPT1 and OsSPL14 will be study. Molecular mechanism of the NPT1-NPT2-OsSPL14 module regulating rice plant type will be analyzed. The discovery of elite allele will help to provide theoretical basis and important genetic resources for molecular breeding of the ‘New Plant Type’ rice.

水稻是重要的粮食作物之一，其产量的稳定和提高关系着我国乃至全球的粮食安全。随着耕地面积减少，持续提高水稻总产量唯有依靠单产的提高。水稻株型改良是水稻高产育种的主攻方向之一，揭示水稻株型形成的遗传调控网络将为品种选育提供理论基础。在前期研究中，本研究组利用国际水稻所的理想株型材料克隆了水稻新株型基因NPT1（New Plant Type 1）。采用相似策略，我们获得了一个同时控制水稻株型和产量的新基因，命名为NPT2。研究发现NPT2能与NPT1蛋白互作。在此基础上，本项目拟重点研究NPT2调控水稻株型的分子机制。利用RNA-seq分析NPT1和NPT2共同调控的下游基因及其网络，深入研究NPT1-NPT2蛋白互作的生物学意义，揭示NPT1-NPT2-OsSPL14分子模块调控水稻株型的新机制，挖掘优异等位基因为“新株型”高产水稻的分子设计育种提供理论基础和具育种利用价值的重要基因资源。

水稻是重要的粮食作物之一，其产量的稳定和提高关系着我国乃至全球的粮食安全。随着耕地面积减少，持续提高水稻总产量唯有依靠单产的提高。水稻株型改良是水稻高产育种的主攻方向之一，揭示水稻株型形成的遗传调控网络将为品种选育提供理论基础。在前期研究中，本研究组利用国际水稻所的理想株型材料克隆了水稻新株型基因NPT1（New Plant Type 1）。采用相似策略，我们获得了一个同时控制水稻株型和产量的新基因，命名为NPT2。研究发现NPT2能与NPT1蛋白互作。本项目研究了NPT2基因的基本特征及生物学功能，重点探讨了NPT2调控水稻株型的分子机制。项目还明确了NPT1和NPT2蛋白的关系，利用RNA-seq找到了NPT1和NPT2共同调控的下游基因，深入研究了NPT1-NPT2蛋白互作的生物学意义，通过转基因和遗传杂交阐明了NPT1、NPT2和OsSPL14的遗传互作关系，最终揭示了NPT1-NPT2-OsSPL14分子模块调控水稻株型的新机制。本研究尝试了运用CRIPSR技术获得了NPT2的一个新的优良等位变异，为优异育种材料的选育和创制提供线索。总的来说，本项目挖掘的优异等位基因为“新株型”高产水稻的分子设计育种提供理论基础和具育种利用价值的重要基因资源。