Study the mechanisms of histone deacetylase HD2s in response to drought stress in plants

在真核生物中，核小体是染色质的基本和功能单位。核小体由DNA和组蛋白蛋白组成，DNA包裹在组蛋白八聚体上。组蛋白的N末端经常受到不同的翻译后修饰，如乙酰化。组蛋白乙酰化受组蛋白乙酰转移酶(HAT)和组蛋白脱乙酰酶(HDACs)的调控，组蛋白乙酰转移酶(HAT)催化超乙酰化，组蛋白脱乙酰酶(HDAC)通过去除核心组蛋白上的乙酰基来催化脱乙酰化。研究表明，HDAC控制植物中的一些基本生物学过程，特别是植物的发育和对环境胁迫的反应。组蛋白脱乙酰酶是一组古老的酶，广泛存在于各种生物体中。植物含有一组特定的HDAC，即HD2。HD2在序列和结构上与其他HDAC家族的相似性很低，似乎HD2在不同类型的植物中都很保守。研究表明，HD2参与植物对干旱等非生物胁迫的反应。目前，关于HD2如何调节基因表达以响应环境压力的分子机制知之甚少。在这项研究中，我们将以拟南芥为模式植物，利用分子生物学的方法进行一系列研究，以研究植物对非生物胁迫，特别是对干旱的响应的不同方面。我们将研究不同HD2在植物中的基因表达模式。然后，我们将揭示不同的HD2成员在应对干旱胁迫时的关系和潜在的相互作用。HD2在脱落酸(ABA)介导的干旱反应途径中的作用将被研究。此外，我们还将研究HD2如何调控干旱反应基因。我们的长期研究目标是揭示HD2以及其他类型的HDAC在调节植物对不同环境胁迫反应中的基因表达方面的洞察力和机制。这项研究产生的知识和发现可用于开发耐非生物胁迫的植物和作物。

In eukaryotes, the nucleosome is the basic and functional unit of chromatin. The nucleosome consists of DNA and histone proteins and DNA wraps on the histone octamer. The N-terminal tails of histone proteins are often subjected to different posttranslational modifications, such as acetylation. Histone acetylation is regulated by histone acetyltransferases (HAT) that catalyze hyper acetylation and histone deacetylases (HDACs) that catalyze deacetylation by removing the acetyl group from the core histones. Research has shown that the HDACs control a number of fundamental biological processes in plants, especially plant development and response to environmental stresses. Histone deacetylases are an ancient group of enzymes that are widely present in various organisms. Plants contain a specific group of HDACs, HD2s. HD2s show low levels of similarity in sequence and structure with other HDAC families and it appears HD2s are well conserved in different types of plants. Research has shown that HD2s involve in plant response to abiotic stresses, such as drought. Currently, little is known about the molecular mechanisms of how HD2s regulate gene expression in response to environmental stresses. In this research, we will use Arabidopsis as model plant and conduct a series of research using molecular biology approaches to study different aspects of HD2 in plants in response to abiotic stresses, specifically, in response to drought. We will study gene expression patterns of different HD2s in plants. We will then reveal the relationship and potential interactions of different HD2 members in response to drought stress. The involvement of HD2s in abscisic acid (ABA)-mediated drought responsive pathway will be investigated. Moreover, we will study how HD2s regulate drought response genes. Our long term research goals are to reveal the insights and mechanisms of HD2s as well as other types HDACs in regulating gene expression in plant response to different environmental stresses. The knowledge and findings generated from the research can be used for development of plants and crops for abiotic stress tolerance.