Transcriptional Regulation of Maize Endosperm Development by IDD9 and IDDveg9 Duplicate Genes

IDD9 和 IDDveg9 重复基因对玉米胚乳发育的转录调控

• 批准号: 1121738
• 负责人: Philip Becraft
• 金额: $ 51.09万
• 依托单位: Iowa State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2015-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1121738&HistoricalAwards=false
• 关键词: Transcriptional; Regulation; Maize; Endosperm; Development

Endosperm is the major storage tissue of cereals and is vastly important for human and livestock nutrition and, increasingly, for industrial purposes. Endosperm comprises several different cell types, each with specific biological functions that influence the biochemical composition and agronomic quality of the grain. Understanding how these cell types are specified and elaborated during development could enable the improvement of grain properties through biotechnology or traditional breeding. This project focuses on an endosperm cell type called aleurone. A maize gene was identified that controls the number of aleurone cells as well as the development of aleurone cell characteristics. This gene, called nkd, is duplicated on two different chromosomes and codes for a transcription factor (a protein that regulates other genes) called IDD9/IDDveg9. As such, the function of this gene is to regulate other genes that are important for endosperm development. The project will use molecular and genetic approaches to explore the biological function of the nkd gene in endosperm development. The relative position of this gene in the regulatory hierarchy that controls endosperm development will be ascertained by examining the temporal and spatial expression patterns in normal maize grains compared to mutants that are known to affect specific steps in endosperm development. Genome-wide analysis of gene expression will reveal what genes are regulated by IDD9/IDDveg9. Finally, a link will be explored between the nkd gene and the plant hormone auxin. This research is expected to define key steps and molecules in the regulation of endosperm (aleurone) development.In addition to the biological and potential agronomic implications, important training opportunities will be afforded to young scientists. One postdoctoral fellow, one graduate student, three undergraduate students and three summer interns will contribute to, and benefit from, these research activities. Emphasis will be placed on recruiting from area minority populations.

胚乳是谷物的主要储存组织，对于人类和牲畜的营养极其重要，并且越来越多地用于工业用途。胚乳由几种不同的细胞类型组成，每种细胞类型都具有影响谷物生化成分和农艺品质的特定生物学功能。了解这些细胞类型在发育过程中是如何被指定和精心设计的，可以通过生物技术或传统育种来改善谷物特性。该项目重点研究称为糊粉层的胚乳细胞类型。鉴定出控制糊粉细胞数量以及糊粉细胞特征发育的玉米基因。该基因称为 nkd，在两条不同的染色体上复制并编码称为 IDD9/IDDveg9 的转录因子（调节其他基因的蛋白质）。因此，该基因的功能是调节对胚乳发育重要的其他基因。该项目将利用分子和遗传学方法探索nkd基因在胚乳发育中的生物学功能。该基因在控制胚乳发育的调控体系中的相对位置将通过检查正常玉米籽粒中的时间和空间表达模式与已知影响胚乳发育特定步骤的突变体相比来确定。对基因表达的全基因组分析将揭示哪些基因受 IDD9/IDDveg9 调节。最后，将探讨 nkd 基因和植物激素生长素之间的联系。这项研究预计将确定胚乳（糊粉层）发育调节的关键步骤和分子。除了生物学和潜在的农艺影响外，还将为年轻科学家提供重要的培训机会。一名博士后、一名研究生、三名本科生和三名暑期实习生将为这些研究活动做出贡献并从中受益。重点将放在从地区少数民族人口中招募人员。