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; 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）：寄生线虫仍然是对全世界人类和牲畜的发病率和死亡率的主要原因。控制的负担主要落在化学治疗药物上，但令人震惊的是，对许多抗新虫药物的抗药性越来越普遍。迫切需要新药。 FMRFAMIDE样肽（FLP）是一个复杂的小型，结构相关的无脊椎动物神经肽，它们在所有线虫的神经系统中无处不在。大多数FLP对一系列线虫肌肉产生了明显的有效作用，在低至下午1点的浓度下引起了深刻的收缩和放松。它们的分布和生理效应表明，FLP是对线虫运动，进食和繁殖的控制的基础。因此，他们的受体是吸引人的新型药物靶标。最近，在秀丽隐杆线虫中发现了许多与FLP配体的G蛋白偶联受体（GPCR）。在这里，建议使用此信息来识别寄生线虫suum中的FLP受体。该提案的具体目的是（1）检验以下假设：秀丽隐杆线虫FLP受体具有高度同源性的GPCR在A. suum中表达，并且（2）检验了这些受体的配体是内源性A. suum flps的假设。使用秀丽隐杆线虫序列从Ascaris EST数据库中鉴定出的候选A. Suum FLP受体将使用种族PCR充分表征。这些受体将在异源系统中功能表达，并用已知的A. suum FLP筛选。将使用Flexstation II（分子设备）来鉴定FLP配体，以监测与受体激活相关的升高的细胞内钙水平。这项为期两年的项目的成功完成将在第一个寄生虫神经肽受体上产生结构和功能信息。它将促进进一步的实验，以更好地了解线虫中这个重要的神经递质家族的生物学。它还将为药物开发研究提供底物。