G-protein Coupled Neuropeptide Receptors in Ascaris suum

猪蛔虫中的 G 蛋白偶联神经肽受体

• 批准号: 6854646
• 负责人: Timothy A Day
• 金额: $ 7.26万
• 依托单位: IOWA STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-05-15 至 2007-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6854646
• 关键词: Ascaris; CHO cells; biological signal transduction; calcium; cell surface receptors; chimeric proteins; helminth genetics; helminthic antigen; high throughput technology; neural transmission; neuropeptide receptor; neuropeptides; polymerase chain reaction; protein quantitation /detection; protein structure; receptor expression; transfection /expression vector

DESCRIPTION (provided by applicant): Parasitic nematodes remain a major cause of morbidity and mortality to humans and livestock throughout the world. The burden of control falls mainly on chemotherapeutics but alarmingly, resistance to many anti-nematode drugs is becoming increasingly prevalent. There is pressing need for new drugs. FMRFamide-like peptides (FLPs) are a complex family of small, structurally-related invertebrate neuropeptides that are ubiquitous in the nervous systems of all nematodes. Most FLPs elicit remarkably potent effects on a range of nematode muscles, inducing profound contractions and relaxations at concentrations as low as 1 pM. Their distribution and physiological effects indicate FLPs are fundamental to the control of nematode locomotion, feeding and reproduction. Their receptors are therefore attractive novel drug targets. Recently, a number of G protein-coupled receptors (GPCRs) with FLP ligands have been identified in Caenorhabditis elegans. Here, it is proposed to use this information to identify FLP receptors in the parasitic nematode, Ascaris suum. The specific aims of the proposal are (1) to test the hypothesis that GPCRs with high homology to the C. elegans FLP receptors are expressed in A. suum and (2) to test the hypothesis that the ligands for these receptors are endogenous A. suum FLPs. Candidiate A. suum FLP receptors, identified from the Ascaris EST database through BLAST searches using the C. elegans sequences, will be fully characterized using RACE PCR. These receptors will be functionally expressed in a heterologous system and screened with known A. suum FLPs. FLP ligands will be identified using FLEXstation II (Molecular Devices) to monitor elevated intracellular calcium levels associated with receptor activation. Successful completion of this two-year project would produce structural and functional information on the first parasitic nematode neuropeptide receptor. It would facilitate further experiments to provide a better understanding of the biology of this important family of neurotransmitters in nematodes. It would also provide a substrate for drug development studies.

描述（由申请人提供）：寄生线虫仍然是全世界人类和牲畜发病和死亡的主要原因。控制的负担主要落在化疗药物上，但令人震惊的是，对许多抗线虫药物的耐药性正变得越来越普遍。迫切需要新药。fmrfamily -like peptides （FLPs）是一个复杂的小的、结构相关的无脊椎神经肽家族，在所有线虫的神经系统中普遍存在。大多数FLPs对一系列线虫肌肉产生显著的有效影响，在低至1 pM的浓度下诱导深刻的收缩和松弛。它们的分布和生理效应表明，FLPs对线虫的运动、摄食和繁殖具有重要的控制作用。因此，它们的受体是有吸引力的新型药物靶点。近年来，在秀丽隐杆线虫中发现了许多带有FLP配体的G蛋白偶联受体（gpcr）。在这里，我们建议利用这些信息来鉴定寄生线虫，蛔虫的FLP受体。本研究的具体目的是：(1)验证与秀丽隐杆线虫FLP受体高度同源的gpcr在秀丽隐杆线虫中表达的假设；(2)验证这些受体的配体是内源性秀丽隐杆线虫FLP受体的假设。候选A. suum FLP受体，通过BLAST搜索从Ascaris EST数据库中使用秀丽隐杆线虫序列鉴定，将使用RACE PCR完全表征。这些受体将在异源系统中功能表达，并用已知的a . susum FLPs进行筛选。FLP配体将使用FLEXstation II （Molecular Devices）来监测与受体激活相关的细胞内钙水平升高。这个为期两年的项目的成功完成将产生首个寄生线虫神经肽受体的结构和功能信息。这将有助于进一步的实验，以更好地了解线虫中这一重要神经递质家族的生物学。它还将为药物开发研究提供基质。