New Vistas in Vitamin K Metabolism

维生素 K 代谢的新前景

基本信息

批准号：
8477918
负责人：
Allan Edward Rettie
金额：
$ 28.77万
依托单位：
UNIVERSITY OF WASHINGTON
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：
2013-07-05 至 2017-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8477918
关键词：
Adopted Affect Anabolism Anticoagulants Automobile Driving Biochemical Biochemical Reaction Biological Biological Assay Blood Clot Blood coagulation Cancer Patient Catabolism Cell Line Cell model Cells Chemicals Chronic Kidney Failure Cytochrome P450 Data Development Diet Dimethylallyltranstransferase Engineering Enzymatic Biochemistry Enzymes Event Extrahepatic Factor IX Fat-Soluble Vitamin Foundations Fracture Future Genes Genetic Genetic Variation Genotype Goals Hand Hemostatic function Hepatic Hepatocyte Homeostasis Human Hydroquinones Hydroxylation Individual Knowledge Label Laboratories Link Liver Mass Spectrum Analysis Measures Metabolic Metabolism Mixed Function Oxygenases Nutrient Oral Pathway interactions Patients Pharmacogenetics Physiological Population Process Production Proteins RNA Interference Recombinants Relative (related person)Research Research Proposals Risk Risk Factors Role Sampling Series Side Source Supplementation Systems Analysis Testing Therapeutic Tissues Transfection Tumor Suppressor Genes Variant Vascular calcification Vitamin K Vitamin K 1 Vitamin K 2 Vitamin K Deficiency Warfarin analog base bone health bone metabolism calcification cancer therapy carboxylate carboxylation cell growth regulation cellular engineering cofactor combat coronary artery calcification dietary constituent enzyme activity genetic variant human tissue hydroquinone in vivo inhibitor/antagonist insight interest men mutant novel public health relevance response soft tissue tool

项目摘要

DESCRIPTION (provided by applicant): The long-term aim of this research is to define the network of integrated metabolic events that underlie vitamin K anabolism and catabolism, in order to understand inter-subject variability in response to this essential dietary nutrient. In ths new application, we will establish the P450 enzymes, CYP4F2 and CYP4F11 as the key vitamin K hydroxylases that initiate catabolism of this essential dietary constituent. In addition, we will determine the role of the newly identified human UBDIA1 enzyme in the interconversion of vitamins K1 and K2. These efforts will establish the link between the core vitamin K cycle proteins and ancillary enzymes that modulate the availability of the hydroquinone cofactors that drive Gla protein production. Because there is a high degree of inter-individual variability in response to supplementation with vitamin K in highly vulnerable K-deficient populations (e.g. those suffering from chronic kidney disease, cancer patients), these studies are of high significance. The goals of this research proposal are three-fold, (i) to establish the relative roes of human CYP4F2 and CYP4F11 in the initiation of vitamin K catabolism, (ii) to establish the role and chemical mechanism of action of UBIAD1 in conversion of vitamin K 1 to K2 (MK-4), and (iii) to ascertain the influence of common genetic variation in each of these three genes on vitamin K homeostatis in human tissues and cellular models of increasing complexity, as a precursor to future in vivo studies. In preliminary studies, we have accomplished the important tasks of heterologous expression of each of the three target enzymes, and development of highly sensitive and specific tandem MS assays for analysis of vitamin K in a variety of biological matrices. With these tools in hand, we propose, in Aim1, to evaluate the roles of CYP4F2 and CYP4F11 in vitamin K catabolism. In Aim 2, we will express and purify human UBIAD1 to enable an unambiguous assessment of the enzyme's catalytic capability and chemical mechanism for conversion of vitamin K1 to K3. In Aim 3, we will use banked, genotyped human liver tissue and a novel engineered cell system for analysis of Gla protein production to determine the effect of common genetic variation in these newly described vitamin K cycle-associated genes on cellular vitamin K homeostasis.

描述（由申请人提供）：本研究的长期目标是确定维生素 K 合成代谢和分解代谢基础的综合代谢事件网络，以便了解受试者对这种必需膳食营养素的反应差异。在这项新应用中，我们将确定 P450 酶、CYP4F2 和 CYP4F11 作为关键的维生素 K 羟化酶，启动这一重要膳食成分的分解代谢。此外，我们将确定新鉴定的人类 UBDIA1 酶在维生素 K1 和 K2 相互转化中的作用。这些努力将建立核心维生素 K 循环蛋白和辅助酶之间的联系，这些辅助酶调节驱动 Gla 蛋白产生的对苯二酚辅助因子的可用性。由于维生素 K 高度缺乏的人群（例如患有慢性肾病、癌症患者）对补充维生素 K 的反应存在很大的个体差异，因此这些研究具有重要意义。本研究提案的目标有三个：(i) 确定人类 CYP4F2 和 CYP4F11 在维生素 K 分解代谢启动中的相对作用，(ii) 确定 UBIAD1 在维生素转化中的作用和化学作用机制K 1 至 K2 (MK-4)，以及 (iii) 确定这三个基因中每一个的常见遗传变异对人体组织和细胞模型中维生素 K 稳态的影响复杂性，作为未来体内研究的先驱。在初步研究中，我们已经完成了三种目标酶中每一种的异源表达的重要任务，并开发了用于分析各种生物基质中维生素 K 的高灵敏度和特异性串联 MS 测定法。有了这些工具，我们在 Aim1 中建议评估 CYP4F2 和 CYP4F11 在维生素 K 分解代谢中的作用。在目标 2 中，我们将表达并纯化人 UBIAD1，以便能够明确评估该酶的催化能力以及将维生素 K1 转化为 K3 的化学机制。在目标 3 中，我们将使用已存储的基因型人类肝脏组织和新型工程细胞系统来分析 Gla 蛋白的产生，以确定这些新描述的维生素 K 循环相关基因中常见遗传变异对细胞维生素 K 稳态的影响。