TaSCL1和TaSPL16调控小麦籽粒发育的作用解析及互作研究

It is crucial in improving the yield of wheat by studying the grain developmental process and discovering genes associated with grain traits. Our preliminary work showed that TaSCL1 and TaSPL16 were differentially expressed during wheat grain developmental process and TaSCL1 could physically interact with TaSPL16, implying a joint regulatory role between them in grain development. In this study, we aimed to resolve their functions in regulating the grain development through multiple methods such as association analysis and transgenic technology. We will sequence TaSCL1 and TaSPL16 genes among diverse wheat varieties, discover their nucleotide polymorphism, and then develop molecular markers to scan different wheat populations, and study their genetic effects through association analysis. Moreover, we will overexpress or knock down the expression of TaSCL1 and TaSPL16 in wheat through transgenic technology, and study their functions in controlling grain traits by phenotypic analysis of transgenic wheat. The emphasis will be focused on the interaction study of TaSCL1 and TaSPL16, including their protein-protein physical interaction, haplotype interplay and genetic interaction among their transgenic plants. In combination with transcriptome sequencing and downstream gene identification, we will construct a molecular regulatory network of TaSCL1 and TaSPL16 in grain development. This study will contribute to clarify regulatory network of wheat grain development, and provide new gene elements for wheat high yield breeding.

研究小麦籽粒的发育过程，发掘控制籽粒性状的相关基因，对提高小麦产量具有重要意义。前期工作发现TaSCL1和TaSPL16在籽粒发育过程中显著差异表达，且它们之间存在蛋白-蛋白物理互作，推测共同参与了籽粒发育过程的调控。本研究拟通过关联分析、转基因技术等多种方法解析TaSCL1和TaSPL16在调控籽粒发育中的作用，利用其核苷酸多态性开发分子标记，扫描小麦不同群体并进行单倍型关联分析，研究其遗传效应；同时获得TaSCL1和TaSPL16 的过表达和抑制表达转基因小麦，根据表型确定这两个基因在调控籽粒相关性状上的作用。重点从蛋白-蛋白物理互作、单倍型互作、转基因植物遗传互作三个层次研究TaSCL1和TaSPL16的互作效应，结合转录组测序和下游基因鉴定，构建TaSCL1和TaSPL16调控籽粒发育的分子网络。预期的研究结果将丰富籽粒发育相关的调控网络，并为小麦的高产育种提供新的基因元件。

研究小麦籽粒的发育过程，发掘控制籽粒性状的相关基因，对提高小麦产量具有重要意义。本项目基于TaSCL1和TaSPL14两个互作蛋白，结合单倍型互作、转基因遗传实验等解析它们在小麦粒重调控中的作用。首先完成了不同小麦品种中TaSCL1（6A、6B、6D）和TaSPL16（7A、7B、7D）的测序分析，并挖掘其核苷酸多态性，开发了相应的分子标记，同时应用分子标记扫描小麦微核心群体和育成品种群体，结合多年多点的农艺性状数据进行单倍型关联分析，发现TaSCL1（6A、6B、6D）和TaSPL16（7A、7B）均存在与高千粒重相关的优异单倍型。获得TaSCL1和TaSPL16的转基因水稻和小麦，发现TaSPL16过表达株系粒重增加，而TaSCL1过表达株系粒重减少，两者在粒重调控上作用相反，同时两者株型上也有显著差异，揭示这两个基因均为一因多效基因，具有改良株型和粒重的应用潜力。鉴定了TaSCL1和TaSPL16在籽粒发育过程中调控的下游基因TaGW7，对其表达调控进行了实验验证，初步构建了TaSCL1和TaSPL16调控籽粒发育的分子网络。本项目的成果包括发表SCI论文5篇，获得中国发明专利授权2项，申请1项。