水稻可塑性基因RPL1调节水稻株高的分子机制研究

Plant height is an important agronomic trait of rice and it is of great significance to crop yield. A variety of hormones, some transcription factors, and miRNAs regulate plant height. Rice plasticity gene (RPL1) may affect phytohormone signaling pathway through epigenetics to regulate the development of rice culms, thus affecting plant height. In this project, we first use RNA-seq technology to analyze gene expression profiles of culms from rpl1 mutant, RPL1-overexpressing plants, and wild-type plants, then obtain genes involved in rice culm development regulated by RPL1. Three genes RPL1R1-3 (RPL1 Related 1-3) related to phytohormones are then selected, and knockout mutants and over-expressing transgenic plants of these genes are obtained and cross with RPL1 transgenic plants. The phenotypes of all experimental plants are examined, and the expression levels and epigenetic modification status of genes related to hormone signaling pathways are investigated in these plants. Finally, the molecular mechanism of RPL1 gene regulating rice culm development is elucidated.

株高是水稻重要的农艺性状，对作物的产量具有重要意义。多种激素、一些转录因子及miRNA，对植物株高都有调控作用。水稻可塑性基因（RICE PLASTICITY 1, RPL1）可能通过表观遗传来影响植物激素信号通路，从而调控水稻茎秆发育，进而影响植株高度。本项目中，首先采用RNA-seq技术，对rpl1突变体、RPL1超量表达及其野生型植株的茎秆进行基因表达谱分析，由此获得受RPL1调控的参与水稻茎秆发育的基因。然后从中选取3个涉及植物激素的基因RPL1R1-3 (RPL1 Related 1-3)，获得这些基因的敲除突变体及超量表达的转基因植株并与RPL1的转基因植株进行杂交。对所得实验材料进行表型检测，并检测激素信号通路相关基因的表达量和表观修饰状态，最终阐明RPL1基因调控水稻茎秆发育的分子机制。

株高是水稻重要的农艺性状，对作物的产量具有重要意义。多种激素、一些转录因子及miRNA，对植物株高都有调控作用。水稻可塑性基因（RICE PLASTICITY 1, RPL1）可能通过表观遗传来影响植物激素信号通路，从而调控水稻茎秆发育，进而影响植株高度。本项目中，首先采用RNA-seq技术，对rpl1突变体及其野生型植株的茎秆进行基因表达谱分析，由此筛选出20个受RPL1调控的参与水稻茎秆发育的基因。然后从中选取3个涉及植物激素的基因，获得其中2个基因（RePRP2.1和RePRP2.2基因）的敲除突变体及超量表达的转基因植株并观测其株高，发现RePRP2.1与RePRP2.2基因共同正调控水稻株高且功能重叠。此外，对另外1个基因（OsIPT4）进行了生物信息学分析，发现它在籼粳亚种间高度分化。