Regulation of mitochondrial heme metabolism by Tmem14c

Tmem14c 对线粒体血红素代谢的调节

基本信息

批准号：
8525515
负责人：
Yvette Y Yien
金额：
$ 5.19万
依托单位：
BRIGHAM AND WOMEN'S HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-06-30 至 2015-06-29
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8525515
关键词：
Acute Erythroblastic Leukemia Affinity Chromatography Anemia Animal Model Biology Carrier Proteins Cell Culture Techniques Cells Child Complex Data Defect Development Disease Drug Metabolic Detoxication Environment Enzymes Erythrocytes Erythroid Erythroid Cells Erythropoiesis Foundations Genes Genetic Goals Health Hematological Disease Hematopoiesis Hematopoietic Heme Heme Iron Hemoglobin Human Iron Label Light Mammalian Cell Mass Spectrum Analysis Mediating Mentors Metabolic Pathway Metabolism Mitochondria Mitochondrial Proteins Mus Organ Oxidation-Reduction Oxygen Pathway interactions Patients Phenotype Play Porphyrias Porphyrins Process Production Pronormoblasts Prosthesis Proteins Public Health Reaction Regulation Research Research Infrastructure Respiration Role Staging Techniques Testing Thin Layer Chromatography Training Uroporphyrinogen III Vertebrates Woman Work Zebrafish coproporphyrinogen III deuteroporphyrin-IX embryonic stem cell erythroid differentiation iron metabolism novel oxygen transport porphyrin metabolism programs protoporphyrin IX public health relevance small hairpin RNA success tool trafficking

项目摘要

DESCRIPTION (provided by applicant): The long-term goal of this project is to identify and characterize novel proteins that regulate mitochondrial heme metabolism, particularly proteins that play a role in mitochondrial heme/porphyrin transport. This project has implications for identifying genetic modifiers for erythroid porphyria and anemia, and thus has public health significance. Our lab has identified Tmem14c as a novel mitochondrial protein that is required for terminal erythroid differentiation and hemoglobinization in vertebrates. Heme synthesis enzymes are present in Tmem14c-deficient murine erythroleukemia (MEL) cells, and preliminary data from our lab indicate that iron transport in Tmem14c-deficient MEL cells is comparable to wild-type MEL cells. However, Tmem14c-deficient MEL cells synthesize decreased levels of heme and protoporphyrin IX. These data suggest that Tmem14c may facilitate mitochondrial porphyrin transport, thereby playing a key role in heme/porphyrin metabolism. In Aim 1, we will test this hypothesis by identifying the block in porphyrin metabolism in Tmem14c deficient cells, comparing the levels of uroporphyrinogen III (cytoplasmic), coproporphyrinogen III (mitochondrial/cytoplasmic) and protoporphyrin IX (mitochondrial) in the mitochondrial and cytoplasmic fractions of wild-type and Tmem14c-deficient MEL cells. In this manner, we will determine if the block in heme synthesis in Tmem14c-deficient cells is a result of defective porphyrin trafficking. As Tmem14c forms higher-order complexes with other proteins, we hypothesize that Tmem14c's interactions with its partners play a crucial role in regulating its function. In Aim 2, we will identify Tmem14c partner and characterize their role in regulating Tmem14c in the heme synthetic pathway; we will identify interacting proteins that are required for terminal erythroid differentiation, heme synthesis and porphyrin transport, and focus on characterizing proteins that regulate Tmem14c's localization and protein stability. Collectively, our studies will contribute to our lon-term objective of understanding regulatory mechanisms controlling heme metabolism, and the interaction of heme metabolism with erythropoiesis. The specific aims in this proposal are of particular significance because studies of Tmem14c function will shed light on the poorly understood porphyrin trafficking pathways that are central to the regulation of heme metabolism and erythropoiesis. These experimental aims are a logical continuation of my graduate work in hematopoiesis, but provide a framework with which to obtain substantial training in the use of the zebrafish as an animal model and additional techniques that will prove invaluable for further studies in erythroid biology.

描述（由申请人提供）：该项目的长期目标是识别和表征调节线粒体血红素代谢的新型蛋白质，尤其是在线粒体血红素/卟啉传输中起作用的蛋白质。该项目对确定红斑和贫血的遗传修饰剂具有影响，因此具有公共卫生的意义。我们的实验室已将TMEM14C鉴定为一种新型的线粒体蛋白，这是脊椎动物中末端红细胞分化和血红蛋白化所必需的。血红素合成酶存在于TMEM14C缺乏的鼠红血症（MEL）细胞中，我们实验室的初步数据表明，TMEM14C缺陷的MEL细胞中的铁转运与野生型MEL细胞相当。但是，TMEM14C缺陷型MEL细胞合成降低血红素和原核IX水平。这些数据表明TMEM14C可能促进线粒体卟啉的转运，从而在血红素/卟啉代谢中起关键作用。在AIM 1中，我们将通过鉴定TMEM14C缺陷细胞中卟啉代谢的阻滞来检验这一假设，并比较尿中核蛋白原III III（细胞质）的水平，核核原III III（cocodrial/cintoplial/cintoplasmic）和原质核酸核酸磷酸核酸磷酸酯和菌粒粒粒粒粒粒粒粒粒粒粒粒粒粒粒细胞膜和菌丝体。野生型和TMEM14C缺陷的MEL细胞的馏分。以这种方式，我们将确定TMEM14C缺陷型细胞中血红素合成的块是否是卟啉运输缺陷的结果。由于TMEM14C与其他蛋白质形成高阶复合物，我们假设TMEM14C与其伴侣的相互作用在调节其功能方面起着至关重要的作用。在AIM 2中，我们将确定TMEM14C伴侣并表征它们在调节血红素合成途径中TMEM14C中的作用。我们将确定末端红细胞分化，血红素合成和卟啉转运所需的相互作用蛋白质，并专注于表征调节TMEM14C定位和蛋白质稳定性的蛋白质。总的来说，我们的研究将有助于我们理解控制血红素代谢的调节机制，以及血红素代谢与促红细胞生成的相互作用。该提案中的具体目的特别重要，因为对TMEM14C功能的研究将揭示出对调节血红素代谢和红细胞生成的核心的知识较低的卟啉运输途径。这些实验目的是我在造血研究中的研究生工作的逻辑延续，但提供了一个框架，以获得斑马鱼用作动物模型的实质性培训和其他技术，这些技术对于进一步的红斑生物学研究而言是无价的。