Frascati-mediated Iron Metabolism in Erythroblasts

该建议的目的是确定相互作用的蛋白质伙伴和生化途径的 线粒体金属转运蛋白及其在红系发育中的作用。生物化学和 参与发育中的成红细胞的线粒体铁代谢的蛋白质知之甚少。 斑马鱼frascati基因的突变导致了严重的低色素性贫血， 原成红细胞期。使用定位克隆策略，我们发现弗拉斯卡蒂编码一种新的 线粒体溶质载体家族（SLC25）成员。frascati基因在胎儿和胎儿中高度表达， 斑马鱼和小鼠的成体造血组织。从脆性缺失ES细胞产生的成红细胞 表现出成熟停滞，55 Fe与血红素的结合严重受损。产生的小鼠突变体 通过有针对性地破坏Frascati基因座，从而证实其在严重贫血中的重要作用， 哺乳动物红细胞发育我们发现弗拉斯卡蒂是将铁输送到 在发育中的红系细胞中用于血红素和Fe-S簇生物合成的线粒体。这个目标 一项建议是确定Frascati转运蛋白的生化途径和相互作用的蛋白质伴侣， 进一步加深了我们对发育中红细胞线粒体铁代谢的理解。的识别 frascati作为一个重要的线粒体铁转运蛋白及其相互作用的蛋白质将提供强大的 用于探索人类铁代谢和红细胞生成障碍的遗传工具。我们建议实现 这些目标包括以下两个具体目标： 具体目标1：将鉴定和表征弗拉斯卡蒂转运蛋白的蛋白质相互作用伴侣。 具体目标2：斑马鱼胚胎和缺乏转录因子的小鼠细胞的比较转录组分析 将进行弗拉斯卡蒂运输。

The objective of this proposal is to identify the interacting protein partners and biochemical pathway of the frascati mitochondrial metal transporter and their role in erythroid development. The biochemistry and proteins involved in mitochondrial iron metabolism of developing erythroblasts are poorly understood. Mutations in the zebrafish frascati gene lead to a profound hypochromic anemia and maturation arrest at the pro-erythroblast stage. Using a positional cloning strategy, we showed that the frascati encodes a novel member of the mitochondrial solute carrier family (SLC25). The frascati gene is highly expressed in fetal and adult hematopoietic tissues of zebrafish and mouse. Erythroblasts generated from frascati-null ES cells exhibit maturation arrest with severely impaired incorporation of 55Fe into heme. Mouse mutants generated by targeted disruption of the frascati locus die of severe anemia, thereby confirming its essential role in mammalian erythroid development. We showed that frascati is the major transporter for delivering iron into the mitochondria for heme and Fe-S cluster biosynthesis in developing erythroid cells. The goal of this proposal is to identify the biochemical pathway and interacting protein partners of the frascati transporter to further our understanding of mitochondrial iron metabolism in developing red cells. The identification of frascati as an essential mitochondrial iron transporter and its interacting proteins will provide powerful genetic tools for exploring human disorders of iron metabolism and erythropoiesis. We propose to achieve these aims by the following two specific aims: Specific Aim 1: Protein interacting partners of the frascati transporter will be identified and characterized. Specific Aim 2: A comparative transcriptome analysis of zebrafish embryos and mouse cells deficient for the frascati transporter will be conducted.