Role of a Putative Histone Demethylase in the Ethylene Signaling Network

假定的组蛋白去甲基化酶在乙烯信号网络中的作用

• 批准号: 7486601
• 负责人: Elizabeth Purdy Howell
• 金额: $ 4.68万
• 依托单位: SALK INSTITUTE FOR BIOLOGICAL STUDIES
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-03-01 至 2010-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7486601
• 关键词: Agriculture; Alleles; Area; Binding Sites; Biology; Chromatin; Complementary DNA; Coupled; DNA; Economics; Enhancers; Enzymes; Epigenetic Process; Ethylene; Ethylenes; Exhibits; Family; Fruit; Genes; Genetic; Genetic Screening; Genetic Transcription; Genome; Genomics; Goals; Histones; Homologous Gene; Human; Knowledge; Length; Link; Lysine; Malignant Neoplasms; Mammals; Methylation; Modification; Pathway interactions; Phenotype; Physiological; Plant Growth Regulators; Plants; Proteins; Regulation; Role; Sequence Analysis; Signal Pathway; Signal Transduction; Signal Transduction Pathway; Site; Somatotropin; System; Techniques; Technology; Work; Yeasts; Zinc Fingers; chromatin immunoprecipitation; chromatin remodeling; human disease; improved; in vitro Assay; interest; loss of function; mutant; novel; pathogen; research study; response; tool; yeast two hybrid system

DESCRIPTION (provided by applicant): The plant hormone ethylene regulates a variety of morphological and physiological responses important for plant survival. The aims of this proposal serve to define the role of EIN6, which functions in an unresolved section of the ethylene signaling pathway. However, tools and approaches proposed in these experiments will have implications for many areas of plant biology and beyond. Preliminary sequence analysis reveals that EIN6 contains Jumonji domains and zinc-finger domains, suggesting a role as a chromatin remodeling enzyme. Specifically, EIN6 contains a Jumonji domain that is closely related to the JARID1 family of mammalian histone demethylases, which have recently been shown to demethylate Histone 3 Lysine 4 (an epigenetic mark associated with active transcription). Histone methylation is an area of particular interest given that this epigenetic modification is connected to cellular aberrations associated with cancer. We propose the use of chromatin immunoprecipitation (ChIP) coupled to target DNA identification through Solexa sequencing technology as an unbiased approach to identify EIN6 target sequences at the genomic level. Our proposed in vitro assay will determine if EIN6 does possess demethylase activity, which would be the first example of a histone demethylase in plants and add an interesting level of regulation to ethylene signaling. Our efforts to understand the mechanism by which EIN6 influences the ethylene response includes using a genetic approach to identify proteins that interact with EIN6 and a genetic screen in planta to identify enhancers of the ein6 phenotype. These studies will bring a new level of understanding to ethylene signal transduction and may reveal novel signaling components. With a more complete view of the pathway we may begin to apply our knowledge to agricultural and economic aspects of ethylene signaling, including fruit ripening and response to pathogen attack. The Specific Aims described here are centered on a key plant mutant that is insensitive to the critical growth hormone, ethylene. Defining the role of this previously uncharacterized gene will improve our current understanding of ethylene signaling in plants. This is an important step towards our long-term goal of applying our knowledge to agricultural and economic aspects of ethylene signaling, such as fruit ripening and response to pathogen attack. This protein of interest is predicted to function as a histone demethylase, which puts an intriguing spin on our work as this type of chromatin modification has not been previously described in plants and is linked to many human diseases including cancer.

描述(申请人提供)：植物激素乙烯调节对植物生存重要的各种形态和生理反应。这项提议的目的是定义EIN6的作用，它在乙烯信号通路中一个未解决的部分发挥作用。然而，这些实验中提出的工具和方法将对植物生物学的许多领域和其他领域产生影响。初步的序列分析表明，EIN6含有Jumonji结构域和锌指结构域，表明EIN6具有染色质重塑酶的作用。具体地说，EIN6包含一个Jumonji结构域，该结构域与哺乳动物组蛋白去甲基酶JARID1家族密切相关，最近发现JARID1家族能使组蛋白3赖氨酸4去甲基化(一种与激活转录相关的表观遗传标记)。组蛋白甲基化是一个特别感兴趣的领域，因为这种表观遗传修饰与癌症相关的细胞异常有关。我们建议通过Solexa测序技术将染色质免疫沉淀(ChIP)与靶DNA鉴定相结合，作为一种在基因组水平上鉴定EIN6靶序列的无偏方法。我们提出的体外实验将确定EIN6是否具有去甲基酶活性，这将是植物中第一个组蛋白去甲基酶的例子，并为乙烯信号转导增加一个有趣的调节水平。我们努力了解EIN6影响乙烯反应的机制，包括使用遗传方法识别与EIN6相互作用的蛋白质，并在植物中进行遗传筛选以识别EIN6表型的增强子。这些研究将使人们对乙烯信号转导有一个新的认识，并可能揭示新的信号成分。随着对这一途径有了更全面的了解，我们可能开始将我们的知识应用于乙烯信号的农业和经济方面，包括果实成熟和对病原体攻击的反应。这里描述的具体目标集中在一个对关键生长激素乙烯不敏感的关键植物突变体上。明确这个以前未被描述的基因的作用将提高我们目前对植物中乙烯信号的理解。这是朝着我们的长期目标迈出的重要一步，即将我们的知识应用于乙烯信号的农业和经济方面，如果实成熟和对病原体攻击的反应。这种感兴趣的蛋白质被预测为组蛋白去甲基酶，这为我们的工作带来了有趣的旋转，因为这种类型的染色质修饰以前从未在植物中被描述过，并与包括癌症在内的许多人类疾病有关。