Protist Oxygen Sensing in Human Disease Protist Oxygen Sensing in Human Disease

人类疾病中的原生生物氧传感人类疾病中的原生生物氧传感

基本信息

批准号：
10651752
负责人：
Ira J Blader
金额：
$ 63.45万
依托单位：
STATE UNIVERSITY OF NEW YORK AT BUFFALO
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-07-01 至 2027-06-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10651752
关键词：
Address Aerobic American Amino Acids Binding Proteins Biochemical Biological Assay Blood Brain CUL1 gene Calcium Cell Survival Cell physiology Cells Cellular Stress Characteristics Complex Cues Cullin Proteins Cyst Data Development Dictyostelium Differentiation and Growth Disease Distant Environment Essential Amino Acids Exposure to F-Box Proteins Face Fetus Goals Growth Heart Homeostasis Hydroxylation Hypoxia Hypoxia Inducible Factor Immune response Immunocompromised Host In Vitro Infection Interferon Type II Knowledge Learning Life Ligase Lung Mediating Medical Metabolic Modification Muscle Names Nutrient Organism Oxygen Parasites Pathway interactions Peptide Elongation Factor 2 Phosphorylation Phosphotransferases Polyubiquitin Procollagen-Proline Dioxygenase Proliferating Proline Protein Biosynthesis Proteins Proteome Protozoa Publishing RBX1 gene Resistance Retina Shapes Stream Stress Testing Tissues Toxoplasma Toxoplasma gondii Ubiquitin Ubiquitination Virulence Work cytokine extracellular genome analysis human disease in vivo mutant new therapeutic target novel therapeutics pathogen phyA phytochrome phyB phytochrome recruit response transcription factor ubiquitin ligase ubiquitin-protein ligase

Address Aerobic American Amino Acids Binding Proteins Biochemical Biological Assay Blood Brain CUL1 gene Calcium Cell Survival Cell physiology Cells Cellular Stress Characteristics Complex Cues Cullin Proteins Cyst Data Development Dictyostelium Differentiation and Growth Disease Distant Environment Essential Amino Acids Exposure to F-Box Proteins Face Fetus Goals Growth Heart Homeostasis Hydroxylation Hypoxia Hypoxia Inducible Factor Immune response Immunocompromised Host In Vitro Infection Interferon Type II Knowledge Learning Life Ligase Lung Mediating Medical Metabolic Modification Muscle Names Nutrient Organism Oxygen Parasites Pathway interactions Peptide Elongation Factor 2 Phosphorylation Phosphotransferases Polyubiquitin Procollagen-Proline Dioxygenase Proliferating Proline Protein Biosynthesis Proteins Proteome Protozoa Publishing RBX1 gene Resistance Retina Shapes Stream Stress Testing Tissues Toxoplasma Toxoplasma gondii Ubiquitin Ubiquitination Virulence Work cytokine extracellular genome analysis human disease in vivo mutant new therapeutic target novel therapeutics pathogen phyA phytochrome phyB phytochrome recruit response transcription factor ubiquitin ligase ubiquitin-protein ligase

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项目摘要

Sensing and responding to changes in environmental oxygen is critical for aerobic organisms. Metazoans accomplish this by destabilizing a transcription factor called hypoxia inducible factor (HIF) in oxygen sufficiency. This is achieved by an oxygen-dependent prolyl 4-hydroxylase (PHD) that hydroxylates proline residues in the HIF-1α transcription factor that targets it for ubiquitin-dependent proteasomal degradation. Protozoans have PHDs but lack HIF and thus respond to changes in oxygen differently and we use the evolutionary distant protists Dictyostelium and Toxoplasma to address this question. Initial studies in Dictyostelium revealed that its PHD, DdPHYa, modifies a proline in Skp1, which is a component of the Skp1/Cullin1/F-box protein/Rbx1 polyubiquitin ligase complex. Skp1 prolyl hydroxylation does not affect its stability, but allows it to be modified by a pentasaccharide that acts to alter the repertoire of associated F- Box proteins. Genome analysis and biochemical assays demonstrated that this Skp1 modification pathway is conserved in the protozoan parasite Toxoplasma, but not in metazoans. Loss of Toxoplasma PHYa leads decreases virulence in vivo and decreased growth in vitro under limited O2 and amino acid conditions. Unlike Dictyostelium, Toxoplasma expresses a second PHD, PHYb, which is required for colonization of oxygen rich tissues as well as Toxoplasma growth at high oxygen. In contrast to PHYa, PHYb functions by regulating elongation during protein synthesis and specifically does so at elevated O2 levels. Because of its medical importance, we will focus on Toxoplasma and pursue three specific aims: i) Determine how PHYa mediates growth at low oxygen and amino acids; ii) Define how PHYb regulates elongation; and iii) Test whether PHYa and PHYb work in tandem as an oxygen-sensing rheostat to grow in whatever oxygen tension in encounters as it infects a host and causes disease.

感知和应对环境氧的变化对于有氧生物。后马达人通过破坏转录来实现这一目标因子称为缺氧诱导因子（HIF）的氧气足够。这是实现的通过氧依赖性丙酰4-羟化酶（PHD），羟基盐水脯氨酸 HIF-1α转录因子中的残基，其靶向泛素依赖性蛋白酶体降解。原生动物有PHD，但缺乏HIF，因此做出了反应氧气的变化不同，我们使用进化的远处生物 dictyostelium和toxoplasma解决了这个问题。初步研究 Dictyostelium透露其博士学位DDPHYA修饰了SKP1中的脯氨酸，该脯氨酸是SKP1/CULLIN1/F-box蛋白/RBX1多泛素连接酶的组成部分复杂的。 SKP1羟基羟基化不影响其稳定性，但允许它为通过五糖的修改，该五糖可改变相关的f-的曲目盒蛋白。基因组分析和生化测定表明这一点 SKP1修饰途径在原生动物寄生虫弓形虫中保守，但不在后生动物中。弓形虫的丧失phya导致病毒降低在有限的O2和氨基酸条件下，体内和体外生长增加。与Dictyostelium不同，Toxoplasma表达第二博士学位，Phyb，在富含氧组织以及在高氧。与PHYA相反，Phyb通过调节伸长来发挥作用在蛋白质合成期间，并在O2升高的水平上进行了专门进行。因为其医学重要性，我们将专注于弓形虫，并追求三个特定的特定目的：i）确定PHYA如何介导低氧气和氨基酸的生长； ii）定义Phyb如何调节伸长率； iii）测试Phya和Phyb是否作为氧气的氧气状阻尼仪在串联中的串联工作，以在任何氧气中生长遭遇的张力是因为它感染了宿主并引起疾病。