The Role of eIF4E Family Members in Zebrafish

eIF4E 家族成员在斑马鱼中的作用

• 批准号: 0134013
• 负责人: Rosemary Jagus
• 金额: --
• 依托单位: University of Maryland Biotechnology Institute
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-02-01 至 2007-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0134013&HistoricalAwards=false
• 关键词: Role; eIF4E; Family; Members; Zebrafish

The translational initiation factor eIF4E is a central component in the initiation and regulation of translation in eukaryotic cells. Through its interaction with the 5' cap structure of mRNA and its translation partner, eIF4G, eIF4E functions to recruit mRNAs to the ribosome. The rapid accumulation of vertebrate EST and genome sequences has allowed the identification of multiple eIF4E family members. Based on sequence homologies and/or function, three classes of eIF4E have been recognized; Class I (archetypal eIF4E and sub-types), Class II (eIF4ELP/HP) and Class III (eIF4E-3, vertebrates only). The uncovering of multiple eIF4E related proteins suggests an unexpected complexity of the mRNA recruitment step and its regulation in vertebrates and has exemplified the difficulties in annotating DNA sequences on the basis of sequence homologies only. One hypothesis is that each form fills a specialized niche in the recruitment of capped mRNAs by the ribosome. Alternatively, it is possible that not all eIF4E family members function as initiation factors or in translational regulation directly, but in an unrelated function such as RNA/RNP export or RNA splicing. The overall goal of this project is to use the knowledge of eIF4E family members and unique reagents accumulated by the Jagus laboratory to elucidate their respective roles in the regulation of gene expression in higher eukaryotes. The objectives are to characterize the functions of eIF4E family members and determine their role in the regulation of gene expression through the following specific aims: 1) analysis of expression pattern of each family member in different tissues and at various developmental stages; 2) determination of the function of each eIF4E family member (from zebrafish and mammals) in translation using a variety of established assays; and 3) kinetic analyses of the interaction of each class with cap-structures, eIF4G and the 4EBPs.The production of cellular proteins begins with the template genetic code that is copied in the form of mRNA. The information encoded by mRNA is translated on the ribosomes into proteins. Control of the recruitment of mRNA by ribosomes is an important form of regulation of gene expression in animal cells. Several protein factors are required for the recruitment of mRNA by the ribosome, the most important of which is the translation factor eIF4E. eIF4E recognizes and binds to the cap structure at the 5' end of mRNA. The accumulation of DNA sequence data has allowed the Jagus laboratory to recognize three classes of eIF4E; Class I (prototypical eIF4E and sub-types), Class II (eIF4ELP/HP) and Class III (eIF4E-3, vertebrates only). The overall goal of this project is to characterize the functions of eIF4E family members and determine their role in the regulation of gene expression in the zebrafish developmental system.

翻译起始因子 eIF4E 是真核细胞翻译起始和调节的核心成分。 通过与 mRNA 的 5' 帽结构及其翻译伙伴 eIF4G、eIF4E 的相互作用，eIF4E 可以将 mRNA 募集至核糖体。 脊椎动物 EST 和基因组序列的快速积累使得能够鉴定多个 eIF4E 家族成员。 根据序列同源性和/或功能，eIF4E 已被识别为三类： I 类（原型 eIF4E 和子类型）、II 类（eIF4ELP/HP）和 III 类（eIF4E-3，仅限脊椎动物）。 多种 eIF4E 相关蛋白的发现表明，脊椎动物中 mRNA 募集步骤及其调节具有意想不到的复杂性，并举例说明了仅根据序列同源性注释 DNA 序列的困难。 一种假设是，每种形式都在核糖体募集加帽 mRNA 的过程中填补了一个专门的生态位。 或者，可能并非所有 eIF4E 家族成员都直接充当起始因子或翻译调节，而是发挥不相关的功能，例如 RNA/RNP 输出或 RNA 剪接。 该项目的总体目标是利用Jagus实验室积累的eIF4E家族成员的知识和独特的试剂来阐明它们各自在高等真核生物基因表达调控中的作用。 目的是通过以下具体目的来表征eIF4E家族成员的功能并确定其在基因表达调控中的作用：1）分析每个家族成员在不同组织和不同发育阶段的表达模式； 2) 使用各种已建立的测定法确定每个 eIF4E 家族成员（来自斑马鱼和哺乳动物）在翻译中的功能； 3) 每一类与帽结构、eIF4G 和 4EBP 相互作用的动力学分析。细胞蛋白质的产生始于以 mRNA 形式复制的模板遗传密码。 mRNA 编码的信息在核糖体上翻译成蛋白质。 核糖体募集 mRNA 的控制是动物细胞中基因表达调节的重要形式。 核糖体募集 mRNA 需要多种蛋白质因子，其中最重要的是翻译因子 eIF4E。 eIF4E 识别并结合 mRNA 5' 端的帽子结构。 DNA 序列数据的积累使 Jagus 实验室能够识别三类 eIF4E： I 类（原型 eIF4E 和子类型）、II 类 (eIF4ELP/HP) 和 III 类（eIF4E-3，仅限脊椎动物）。 该项目的总体目标是表征 eIF4E 家族成员的功能，并确定它们在斑马鱼发育系统基因表达调节中的作用。