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: 8698411
• 负责人: Anjaparavanda P Naren
• 金额: $ 30.54万
• 依托单位: CINCINNATI CHILDRENS HOSP MED 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 2015-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8698411
• 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（由申请方提供）：该提案的统一假设是2型溶血磷脂酸受体（LPA 2受体）和Na+/H+交换调节因子-2（NHERF 2）的大分子复合物在分泌性腹泻的致病过程中起重要作用。我们的目的是研究在生理和病理生理条件下，在分子水平上的大分子复合物的形成和调节，在霍乱引起的腹泻中发挥关键作用。此外，该研究将研究LPA 2受体介导的信号传导事件调节细胞中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LPA 2受体主要在肠腔表面表达并在某些形式的胃肠疾病中下调的假设，并检验LPA 2受体激活抑制质膜区室化cAMP生成的假设。目标二：为了检验LPA可以通过将其进一步聚集到质膜上的微结构域来调节含LPA 2的大分子复合物的形成以及该过程由NHERF 2依赖性蛋白质-蛋白质相互作用介导的假设，目的3：为了验证通过沉默NHERF 2破坏大分子复合物改变质膜上的区室化cAMP水平以及体内NHERF 2敲除小鼠产生的cAMP水平的假设，对CTX的反应改变了cAMP。这一发现对于从分子水平上了解分泌性中耳炎的致病过程和可能的治疗干预具有重要意义。该研究在概念上和技术上都具有很高的创新性。