A Comprehensive Study of the Maize Shoot Apex - Deciphering Genes Underlying Shoot Apical Meristem Allometry

营养枝顶端分生组织(SAM)负责植物枝条中所有器官的发育。此外，SAM的形状和大小(异速生长)可以预测在农学上重要的成株性状，这意味着SAM中作用的调节机制可以用于指导作物改良计划。这项建议的目的是利用玉米现有的大量基因组资源来定义调节SAM结构及其在干细胞维持和器官发生中的功能的遗传网络。高分辨率图像分析将用于全基因组关联研究，以确定与玉米SAM结构中存在的巨大自然变异相关的基因。此外，我将进行RNA图谱分析，以确定现代农业中常见的高密度种植所诱导的基因表达差异，这些种植已知会显著改变SAM异速生长。这些数据将与玉米地上部基因表达图谱中特定区域的转录数据和反向遗传分析相结合，以全面了解调控SAM结构和功能的分子网络，并揭示网络组件如何响应种植密度增加带来的环境变化。已确定的基因将突出候选选择目标，以进一步改进育种，提高生物质产量和产量。

The vegetative shoot apical meristem (SAM) is responsible for the development of all organs in the plant shoot. Furthermore, SAM shape and size (allometry) is predictive of agronomically-important adult plant traits, implying that regulatory mechanisms acting in the SAM can be used to guide crop improvement programs. The goal of this proposal is to take advantage of the tremendous genomic resources available in maize to define genetic networks that regulate SAM structure and its function in stem cell maintenance and organogenesis. High-resolution image analysis will be used in genome-wide association studies (GWAS) to identify genes associated with the tremendous natural variation in SAM architecture present in maize. In addition, I will perform RNA profiling to define gene expression differences induced by high-density plantings common in modern agriculture that are known to significantly alter SAM allometry. These data will be combined with domain-specific transcriptomic data from the maize shoot gene expression atlas and reverse genetic analyses, to come to a comprehensive understanding of the molecular networks that regulate SAM structure and function, and to reveal how network components respond to environmental change imposed by increased planting density. The genes identified will highlight candidate targets for selection to further improve breeding towards increased biomass production and yield.