Activities and Functions of the Basic Pentacysteine DNA-binding Proteins

蛋白质编码基因的转录是一个基本的细胞过程，对新陈代谢和发育的各个方面都是必不可少的。因此，了解dna结合转录因子促进和调节基因差异转录的机制是分子和发育生物学家的主要目标。BASIC PENTACYSTEINE （BPC）蛋白是一个新发现的植物特异性dna结合蛋白小家族，在大多数植物器官中产生。导致BPC基因突变或过表达的表型效应表明，BPC蛋白在多种基因的表达中发挥作用。BPC蛋白功能的表征有望揭示dna结合蛋白功能的新信息和基因转录调控的新机制。将采用多学科方法来确定BPC蛋白的细胞作用。BPC作用的直接靶标将通过一种“自上而下”的方法来确定，即识别在BPC突变植物中表达改变的基因。其他筛选将利用转基因植物中表达的有条件活性BPC变体，并结合全面的基因表达谱。一种互补的“自下而上”的方法将从可以被体外分离的BPC蛋白结合的序列开始识别BPC靶标。dna结合转录因子的活性通常源于与其他蛋白因子的关联。体内系统将用于确定与BPC蛋白结合的蛋白质的性质，以确定BPC蛋白调节基因表达的机制。该项目的完成将为植物基因表达决定因素提供重要的新信息。BPC蛋白的新性质和它们具有独特的dna结合结构域的事实为揭示蛋白质- dna相互作用的新基础信息提供了机会。参与研究的本科生、研究生和博士后将学习应用分子生物学的最新方法，并在强大的生物学背景下分析基因表达。高中学生也将通过实验室实习和首席研究员的外展接触到这一前沿研究。

Transcription of protein coding genes is a fundamental cellular process that is essential for all aspects of metabolism and development. Understanding of the mechanisms by which DNA-binding transcription factors promote and regulate differential transcription of genes is therefore a major goal of molecular and developmental biologists. The BASIC PENTACYSTEINE (BPC) proteins are a newly described small family of plant-specific DNA-binding proteins that are produced in most plant organs. Phenotypic effects resulting in mutation or overexpression of BPC genes indicate that BPC proteins play roles in expression of a variety of genes. Characterization of the function of the BPC proteins promises to reveal new information on functions of DNA-binding proteins and novel mechanisms for regulation of gene transcription. A multidisciplinary approach will be used to determine the cellular roles of BPC proteins. Direct targets of BPC action will be identified through a "top-down" approach by identifying genes whose expression is altered in bpc mutant plants. Additional screens will make use of conditionally active BPC variants expressed in transgenic plants in combination with comprehensive gene expression profiling. A complementary "bottom-up" approach will identify BPC targets starting from sequences that can be bound by isolated BPC proteins in vitro. The activity of DNA-binding transcription factors commonly results from association with additional protein factors. In vivo systems will be used to determine the nature of proteins bound by BPC proteins to determine the mechanisms through which BPC proteins modulate gene expression.Completion of the project will provide significant new information on the determinants of gene expression in plants. The novel nature of the BPC proteins and the fact that they have a unique DNA-binding domain provides the opportunity to uncover new fundamental information on protein-DNA interactions. Undergraduate, graduate and postdoctoral participants in the research will learn to apply the latest methods of molecular biology and analysis of gene expression in a strong biological context. High school students will also be exposed to this cutting edge research through lab internships and outreach by the principal investigator.