EAGER: Molecular Genetic Analysis of Early Endosperm Development by Microinjection of Maize Embryo Sacs

EAGER：玉米胚囊显微注射早期胚乳发育的分子遗传学分析

• 批准号: 0918170
• 负责人: Brian Larkins
• 金额: $ 30万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-03-01 至 2012-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0918170&HistoricalAwards=false
• 关键词: EAGER; Molecular; Genetic; Analysis; Early

Endosperm development in grasses has several distinct phases: early development, comprising double fertilization, syncytium formation, and cellularization; differentiation, which includes the formation of the main cell types (transfer cells, aleurone, starchy endosperm, and embryo-surrounding cells), the periods of mitosis and endoreduplication, and the accumulation of storage compounds; and maturation, which includes programmed cell death, dormancy, and desiccation. Mutant analysis has provided knowledge regarding genes that influence the differentiation and maturation phases of endosperm development, but much less is known about early development and its consequences. Studies in maize and wheat suggest the extent of cell division during early development plays an important role in grain yield, but little is known about its genetic basis. While it is difficult to study early endosperm development in most cereals, this is easier with maize, because the embryo sac can be isolated and the endosperm cultured in vitro. This project seeks to develop a novel method to investigate early development in maize endosperm by microinjecting nucleic acids into 2-3 days after pollination (DAP) embryo sacs. This approach has advantages for transforming endosperm because it does not require the time and labor-intensive procedures associated with current methods of producing transgenic maize plants. There are risks associated with these experiments, but if successful could be transformative for identifying the genetic mechanisms that regulate early endosperm development and the results, which can be accessed at http://ag.arizona.edu/research/larkinslab/index.htm, could have valuable practical applications.

禾本科植物胚乳的发育有几个不同的阶段：早期发育，包括双受精、合胞体形成和细胞化;分化，包括主要细胞类型的形成（传递细胞、糊粉层、淀粉质胚乳和胚周围细胞）、有丝分裂和核内复制期以及贮藏化合物的积累;和成熟，包括程序性细胞死亡、休眠和脱水。突变体分析提供了关于影响胚乳发育的分化和成熟阶段的基因的知识，但对早期发育及其后果知之甚少。对玉米和小麦的研究表明，早期发育过程中细胞分裂的程度对谷物产量起着重要作用，但对其遗传基础知之甚少。虽然在大多数谷物中研究早期胚乳发育是困难的，但用玉米进行研究比较容易，因为可以分离胚囊并在体外培养胚乳。本项目旨在通过将核酸显微注射到授粉后2-3天（DAP）的胚囊中，开发一种研究玉米胚乳早期发育的新方法。这种方法对于转化胚乳具有优势，因为它不需要与目前生产转基因玉米植物的方法相关的时间和劳动密集型程序。这些实验存在风险，但如果成功，可能对确定调控早期胚乳发育的遗传机制具有变革性意义，其结果可在http：//ag.arizona.edu/research/larkinslab/index.htm上获得，可能具有宝贵的实际应用。