Patterning of the Female Gametophyte in Arabidopsis

拟南芥雌配子体的模式

• 批准号: 0745167
• 负责人: Venkatesan Sundaresan
• 金额: --
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-02-15 至 2011-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0745167&HistoricalAwards=false
• 关键词: Patterning; Female; Gametophyte; Arabidopsis

PI: Venkatesan SundaresanProposal Number: IOS-0745167Title: Patterning of the female gametophyte in ArabidopsisAbstractThe reproduction of flowering plants relies on the production of gametophytes, the haploid phase of the plant life cycle generated by the reproductive organs of the flower, containing half the chromosome set of the parent plant. Seed formation requires that female gametophytes called embryo sacs, be fertilized by male gametophytes which are pollen grains containing sperm cells. The mature female gametophyte or embryo sac consists of only four cell types, including two gametes ? the egg cell and central cell, resulting from the execution of a precise developmental program. This project will use the model plant Arabidopsis to study the molecular mechanisms that govern the formation of developmental pattern in the embyo sac. An unusual mutation, eostre, in which the embryo sac has an additional egg cell in place of another cell called a synergid cell, has been identified in Arabidopsis. Characterization of the eostre mutant shows that transcriptional regulators of the BELL and class II Knox homeodomain families, and interacting proteins of the OVATE family, regulate cell specification in the embryo sac. Identification of specific members of these gene families that function in female gametophyte development and their possible roles in specification of cell identities in the embryo sac will be undertaken. In addition, new experimental evidence indicates that signaling by the plant hormone auxin establishes cell identity in the embryo sac. The function of auxin in cell specification in the embryo sac will be further investigated through approaches employing genetic mutants and RNA silencing as well as cellular markers that track auxin concentrations and transport. The proposed studies will provide an understanding of the mechanisms underlying development and function of the female gametophyte. As the embryo sac plays a central role in seed formation, the knowledge gained from these studies has important potential applications towards the control of reproduction and increased seed production in crop plants. The project will also provide comprehensive training in genetics and molecular biology of plant reproduction for postdoctoral fellows, and research opportunities for undergraduate students, including students from underrepresented groups, by providing valuable research experience and training for the life sciences and biotechnology professions.

主要研究者：Venkatesan Sundaresan提案编号：摘要显花植物的繁殖依赖于配子体的产生，配子体是由花的生殖器官产生的植物生命周期的单倍体阶段，含有亲本植物一半的染色体组。 种子的形成需要被称为胚囊的雌配子体被含有精细胞的花粉粒的雄配子体受精。成熟的雌配子体或胚囊只有四种细胞类型，包括两个配子。卵细胞和中央细胞，是执行精确的发育程序的结果。本计画将以模式植物拟南芥为研究对象，探讨胚囊发育模式形成的分子机制。 一种不寻常的突变，eostre，其中胚囊有一个额外的卵细胞代替另一个细胞称为助细胞，已被确定在拟南芥。eostre突变体的表征表明，转录调控的贝尔和II类诺克斯同源结构域的家庭，和相互作用的蛋白质的OVATE家庭，调节胚囊中的细胞规格。 这些基因家族的特定成员，在雌配子体发育中发挥作用，并在胚囊细胞身份的规格可能发挥的作用，将进行鉴定。此外，新的实验证据表明，植物激素生长素的信号在胚囊中建立了细胞身份。 生长素在胚囊细胞特化中的功能将通过采用遗传突变体和RNA沉默以及跟踪生长素浓度和运输的细胞标记的方法进一步研究。 拟议的研究将提供雌配子体的发育和功能的机制的理解。 由于胚囊在种子形成中起着核心作用，因此从这些研究中获得的知识对于控制作物植物的繁殖和增加种子产量具有重要的潜在应用。该项目还将通过为生命科学和生物技术专业提供宝贵的研究经验和培训，为博士后研究员提供植物繁殖遗传学和分子生物学方面的全面培训，并为本科生，包括代表性不足群体的学生提供研究机会。