Frascati: mitochondrial transporter and erythropoiesis

描述（由申请人提供）：本提案的目的是了解frascati（一种新型线粒体溶质转运蛋白（SLC 25））在脊椎动物红细胞生成和铁代谢中的作用。后天性或先天性铁代谢缺陷是最常见的医学疾病之一。斑马鱼frascati基因的突变导致严重的低色素性贫血和原成红细胞阶段的发育停滞。使用定位克隆策略，我们表明，frascati编码的线粒体溶质载体家族的成员。frascati基因（mitoferrin，slc25a37）在斑马鱼和小鼠的胚胎和成体造血组织中高度表达。我们假设frascati负责将铁传递到线粒体，特别是发育中的红系细胞的线粒体。本应用程序的目标是测试这一假设。我们建议通过以下两个具体目标来实现这一目标：具体目标1：分析frascati基因的生化功能。1.1 frascati基因在线粒体铁收购的作用将研究使用永生化细胞和斑马鱼胚胎缺乏frascati活动。1.2通过在大肠杆菌中以包涵体形式表达重组蛋白，研究其生理底物和转运特性。大肠杆菌中的蛋白质及其在蛋白脂质体中的重构。具体目标2：分析哺乳动物中的frascati基因。2.1将通过靶向基因破坏来研究小鼠中frascati基因的功能。对frascati基因功能的深入了解将直接关系到我们对人类缺铁性贫血和铁超载疾病的理解。

DESCRIPTION (provided by applicant): The objective of this proposal is to understand the role of frascati, a novel mitochondrial solute transporter (SLC25), in vertebrate erythropoiesis and iron metabolism. Acquired and congential defects in iron metabolism from either deficiency or excess are one of the most common medical diseases. Mutations in the zebrafish frascati gene lead to a profound hypochromic anemia and a developmental arrest at the pro- erythroblast stage. Using a positional cloning strategy, we showed that frascati encodes a member of the mitochondrial solute carrier family. The frascati gene (mitoferrin, slc25a37) is highly expressed in fetal and adult hematopoietic tissues of zebrafish and mouse. We hypothesize that frascati is responsible for delivering iron to the mitochondria, and in particular, the mitochondria of developing erythroid cells. The goal of this application is to test this hypothesis. We propose to accomplish this goal by the following two specific aims: Specific Aim 1: Analysis of the biochemical function of the frascati gene. 1.1 The role of the frascati gene in mitochondrial iron acquisition will be studied using immortalized cells and zebrafish embryos deficient in frascati activity. 1.2 The physiologic substrate and transport properties of the frascati mitochondrial transporter will be studied by expression of recombinant protein as inclusion bodies in E. coli and their reconstitution in proteoliposomes. Specific Aim 2: Analysis of the frascati gene in mammalian organisms. 2.1 The function of the frascati gene in mouse will be studied by targeted gene disruption. Insight into the function of the frascati gene will be directly relevant to our understanding of human disorders of iron deficiency anemia and iron-overload.