LPA2 receptor-containing complexes in regulating secretory diarrhea

含 LPA2 受体的复合物调节分泌性腹泻

• 批准号: 8500254
• 负责人: Anjaparavanda P Naren
• 金额: $ 0.72万
• 依托单位: UNIVERSITY OF TENNESSEE HEALTH SCI CTR
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-15 至 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8500254
• 关键词: Acute; Affect; Agonist; Animal Model; Apical; Cell Line; Cell membrane; Cells; Cessation of life; Childhood; Chloride Channels; Chloride Ion; Chlorides; Cholera; Cholera Toxin; Complex; Coupled; Cyclic AMP; Cystic Fibrosis Transmembrane Conductance Regulator; Diarrhea; Disease; Edg4 Protein; Elderly; Electrolytes; Epithelial Cells; Event; Exocrine Glands; Fluids and Secretions; Generations; Hospitalization; Human; Incidence; Inflammatory Bowel Diseases; Intestines; Knockout Mice; Lysophosphatidic Acid Receptors; Macromolecular Complexes; Mediating; Modeling; Molecular; Multiprotein Complexes; Mus; Physicians; Physiological; Play; Population; Process; Regulation; Research; Role; Signal Pathway; Signal Transduction; Sodium Chloride; Surface; Testing; Therapeutic Intervention; United States; Visit; Water; attenuation; gastrointestinal epithelium; in vivo; innovation; mouse model; protein protein interaction; receptor expression; receptor-mediated signaling; response; small hairpin RNA; sodium-hydrogen exchanger regulatory factor; technology/technique development

DESCRIPTION (provided by applicant): The unifying hypothesis of this proposal is that macromolecular complex of type 2 lysophosphatidic acid receptor (LPA2 receptor) and Na+/H+ exchange regulatory factor-2 (NHERF2) plays important roles in the pathogenic process of secretory diarrhea. We aim to study the formation and regulation of the macromolecular complex at the molecular level under physiological and pathophysiological conditions that play a critical role in cholera induced diarrhea. Moreover, the research will study the mechanism through which LPA2 receptor- mediated signaling events regulate CFTR-dependent electrolyte secretion in cells and fluid secretion in an animal model of diarrhea. Three aims will be studied: Aim 1: To test the hypothesis that LPA2 receptor is primarily expressed on the luminal surface of the gut and is down regulated in certain forms of diarrheal diseases, and to test the hypothesis that activation of LPA2 receptor inhibits compartmentalized cAMP generation at the plasma membrane. Aim 2: To test the hypothesis that LPA can regulate the formation of the LPA2-containing macromolecular complex by further clustering it to microdomain on the plasma membrane and that the process is mediated by NHERF2-dependent protein-protein interactions Aim 3: To test the hypothesis that disruption of the macromolecular complex by silencing NHERF2 alters compartmentalized cAMP levels at the plasma membrane and that in vivo NHERF2 knockout mice generate altered cAMP in response to CTX. The proposal is of great importance and significance for understanding the pathogenic process of the deadly secretory diarrheal diseases at the molecular level, and for possible therapeutic intervention of the disease. The proposed study is highly innovative in both conceptual advance and in technology/technique development.

描述（申请人提供）：本提案的统一假设是2型溶血磷脂酸受体（LPA2受体）和Na+/H+交换调节因子2（NHERF2）的大分子复合物在分泌性腹泻的发病过程中发挥重要作用。我们的目的是在分子水平上研究在霍乱引起的腹泻中发挥关键作用的生理和病理生理条件下大分子复合物的形成和调节。此外，该研究还将研究 LPA2 受体介导的信号事件调节细胞中 CFTR 依赖性电解质分泌和腹泻动物模型中液体分泌的机制。将研究三个目标： 目标 1：检验 LPA2 受体主要在肠道管腔表面表达并在某些形式的腹泻疾病中下调的假设，并检验 LPA2 受体的激活抑制区室化 cAMP 的假设在质膜上生成。目标 2：检验以下假设：LPA 可以通过进一步将含 LPA2 的大分子复合物聚集到质膜上的微域来调节其形成，并且该过程是由 NHERF2 依赖性蛋白质-蛋白质相互作用介导的。 目标 3：测试假设通过沉默 NHERF2 来破坏大分子复合物会改变质膜上的区室化 cAMP 水平，并且体内 NHERF2 敲除小鼠会产生改变的 cAMP 以响应CTX。该提议对于从分子水平了解致命性分泌性腹泻疾病的发病过程以及对该疾病可能的治疗干预具有重要意义和意义。拟议的研究在概念进步和技术/技术开发方面都具有高度创新性。