Regulation of secretory diarrhea by ER-PM junction signaling

ER-PM 连接信号传导调节分泌性腹泻

• 批准号: 9762913
• 负责人: Alexandra Chang-Graham
• 金额: $ 4.13万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2020-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9762913
• 关键词: Address; Age; Apical; Binding; Biochemical; Biological Models; Biosensor; Calcium; Cell membrane; Cell physiology; Cells; Child; Chloride Channels; Chlorides; Cholera Toxin; Cognitive; Complex; Constipation; Cyclic AMP; Cyclic GMP; Cyclic Nucleotides; Cystic Fibrosis Transmembrane Conductance Regulator; Data; Dehydration; Development; Developmental Delay Disorders; Diarrhea; Dysentery; Endoplasmic Reticulum; Enteral; Epithelial Cells; Fellowship; Fluids and Secretions; Functional disorder; Future; Gastrointestinal Physiology; Gastrointestinal tract structure; Genetic Engineering; Goals; Health; Homeostasis; Human; Human Engineering; Imaging Techniques; Intestines; Ion Channel; Knowledge; Life; Mediator of activation protein; Microscopy; Modeling; Molecular; Morbidity - disease rate; Mus; Nonstructural Protein; Norovirus; Oral Rehydration Therapy; Pharmacology; Physicians; Play; Process; Proteins; Regulation; Research; Research Project Grants; Role; Rotavirus; Rotavirus Infections; STIM1 gene; Scientific Advances and Accomplishments; Scientist; Severity of illness; Signal Pathway; Signal Transduction; Small Intestines; Structure; Testing; Training; Vaccines; Virus; base; clinically relevant; diarrheal disease; extracellular; global health; inhibitor/antagonist; insight; knock-down; live cell imaging; mortality; mouse model; multidisciplinary; overexpression; pathogen; pathogenic bacteria; protein complex; recruit; sensor; skills; small hairpin RNA; tool

PROJECT SUMMARY Secretory diarrhea is a major cause of morbidity and mortality in children resulting from the overstimulation of chloride (Cl-) channels in intestinal epithelial cells (IECs) that leads to overwhelming fluid secretion and life- threatening dehydration. These Cl- channels are regulated by cyclic nucleotides (cAMP and cGMP) and calcium (Ca2+) signaling pathways, but there are gaps in knowledge in how pathogens, such as rotavirus (RV), cause diarrhea through elevation of cytosolic Ca2+ ([Ca2+]c). RV persistently activates stromal interaction molecule 1 (STIM1) in infected cells, which in turn activates processes for extracellular Ca2+ entry at endoplasmic reticulum-plasma membrane (ER-PM) junctions. Activated STIM1 causes formation of ER-PM junction protein complexes that regulate Ca2+ and cAMP signaling and potentially the activation of Ca2+- activated and cAMP-activated chloride channels. Understanding the identity and activation of Cl- channels in RV infection is significant for advancing scientific knowledge of fluid secretion in the GI tract as well as future development of anti-secretory therapies to treat infectious and functional diarrhea. Thus the objective of this research is to identify the Cl- channels activated during RV infection and the regulatory role of activated STIM1 in ER-PM junctional complexes in their activation. I hypothesize that persistent activation of STIM1 stimulates the activation of Ca2+- and cAMP-dependent Cl- channels for RV-induced diarrhea. Using human intestinal enteroids (HIEs) genetically modified with biosensors as a model of IECs and a mouse model of RV diarrhea, I propose [1] to identify the Cl- channels activated during RV infection and [2] to determine the dynamic composition of ER-PM junctions with STIM1 activation in RV-infected IECs. Results from the proposed project will significantly advance our current understanding of molecular mechanisms of Cl- secretion in IECs, which can be extended to study other enteric viruses and bacterial pathogens. These findings will provide new insights into the regulatory roles of ER-PM junctions in the specialization of cell functions.

项目摘要 分泌性腹泻是儿童发病和死亡的主要原因， 肠上皮细胞（IEC）中的氯（Cl-）通道，导致大量液体分泌和生命- 有脱水的危险这些Cl-通道由环核苷酸（cAMP和cGMP）调节， 钙（Ca2+）信号通路，但在病原体，如轮状病毒（RV）， 通过升高胞浆Ca 2+（[Ca 2 +] c）引起腹泻。RV持续激活基质相互作用 分子1（STIM 1）在感染的细胞，这反过来又激活细胞外Ca2+进入的过程， 内质网-质膜（ER-PM）连接。激活的STIM 1导致ER-PM的形成 连接蛋白复合物，调节Ca2+和cAMP信号传导，并可能激活Ca2 +- 激活和cAMP激活的氯离子通道。了解Cl-通道的身份和激活， RV感染对于推进胃肠道液体分泌的科学知识以及未来的研究具有重要意义。 开发抗分泌疗法以治疗感染性和功能性腹泻。因此，这一目标 研究旨在确定RV感染期间激活的Cl-通道以及激活的STIM 1的调节作用 在ER-PM连接复合物的激活中。我假设STIM 1的持续激活 刺激RV诱导的腹泻的Ca2 +-和cAMP-依赖性Cl-通道的活化。使用 用生物传感器遗传修饰的人肠类肠上皮细胞（HIE）作为IEC模型和小鼠模型 对于RV腹泻，我建议[1]确定RV感染期间激活的Cl-通道，[2]确定RV感染期间激活的Cl-通道。 RV感染的IEC中具有STIM 1激活的ER-PM连接的动态组成。结果 建议的项目将大大推进我们目前对Cl-分泌的分子机制的理解 在IEC中，可以扩展到研究其他肠道病毒和细菌病原体。这些发现将 提供了新的见解ER-PM交界处在细胞功能的专业化的监管作用。