Syntaxin 3 is necessary for cAMP- and cGMP-regulated exocytosis of CFTR: implications for enterotoxigenic diarrhea
Syntaxin 3 is necessary for cAMP- and cGMP-regulated exocytosis of CFTR: implications for enterotoxigenic diarrhea
复制标题
DOI：
10.1152/ajpcell.00029.2010
复制
发表时间：
2010-12-01
影响因子：
5.5
通讯作者：
Ameen, Nadia
中科院分区：
文献类型：
--
作者：
Collaco, Anne;Marathe, Jai;Ameen, Nadia
Collaco A、Marathe J、Kohnke H、Kravstov D、Ameen N。 Syntaxin 3 对于 cAMP 和 cGMP 调节的 CFTR 胞吐作用是必需的：对肠毒素性腹泻的影响。 Am J Physiol Cell Physiol 299：C1450-C1460，2010。首次发表于 2010 年 9 月 15 日； doi:10.1152/ajpcell.00029.2010.-霍乱弧菌和大肠杆菌产生的肠毒素在缺乏功能性囊性纤维化跨膜电导调节器 (CFTR) 氯离子通道的情况下不能引起液体分泌。接触肠毒素后，CFTR 通道迅速从内涵体中募集，并通过胞吐插入肠上皮细胞的顶端质膜，使细胞表面的通道数量增加至少四倍。然而，协调 CFTR 胞吐插入质膜的分子机制在很大程度上尚不清楚。本研究使用免疫荧光、免疫印迹、表面生物素化、谷胱甘肽 S-转移酶 (GST) 下拉测定和免疫沉淀来鉴定大鼠空肠和极化肠 Caco-2(BB)e 细胞中环核苷酸激活 CFTR 胞吐作用中胞吐可溶性 N-乙基马来酰亚胺 (NEM) 敏感因子附着受体 (SNARE) 囊泡融合机制的成分。 Syntaxin 3 是一种肠道特异性 SNARE，与 CFTR 共定位于大鼠空肠和极化 Caco-2(BB)e 细胞肠上皮细胞的顶端结构域。免疫共沉淀和 GST 结合研究证实 Syntaxin 3 在体内与 CFTR 相互作用。此外，热稳定肠毒素 (STa) 激活 CFTR 和突触融合蛋白 3 到大鼠空肠表面的胞吐作用。通过短发夹 RNA (shRNA) 干扰沉默突触融合蛋白 3 可消除细胞中环核苷酸刺激的 CFTR 胞吐作用。这些观察结果揭示了突触融合蛋白 3 在肠毒素引起的腹泻的病理生理学中的新的重要作用。
Collaco A, Marathe J, Kohnke H, Kravstov D, Ameen N. Syntaxin 3 is necessary for cAMP-and cGMP-regulated exocytosis of CFTR: implications for enterotoxigenic diarrhea. Am J Physiol Cell Physiol 299: C1450-C1460, 2010. First published September 15, 2010; doi:10.1152/ajpcell.00029.2010.-Enterotoxins elaborated by Vibrio cholerae and Escherichia coli cannot elicit fluid secretion in the absence of functional cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels. After enterotoxin exposure, CFTR channels are rapidly recruited from endosomes and undergo exocytic insertion into the apical plasma membrane of enterocytes to increase the number of channels on the cell surface by at least fourfold. However, the molecular machinery that orchestrates exocytic insertion of CFTR into the plasma membrane is largely unknown. The present study used immunofluorescence, immunoblotting, surface biotinylation, glutathione S-transferase (GST) pulldown assays, and immunoprecipitation to identify components of the exocytic soluble N-ethylmaleimide (NEM)-sensitive factor attachment receptor (SNARE) vesicle fusion machinery in cyclic nucleotide-activated exocytosis of CFTR in rat jejunum and polarized intestinal Caco-2(BB)e cells. Syntaxin 3, an intestine-specific SNARE, colocalized with CFTR on the apical domain of enterocytes in rat jejunum and polarized Caco-2(BB)e cells. Coimmunoprecipitation and GST binding studies confirmed that syntaxin 3 interacts with CFTR in vivo. Moreover, heat-stable enterotoxin (STa) activated exocytosis of both CFTR and syntaxin 3 to the surface of rat jejunum. Silencing of syntaxin 3 by short hairpin RNA (shRNA) interference abrogated cyclic nucleotide-stimulated exocytosis of CFTR in cells. These observations reveal a new and important role for syntaxin 3 in the pathophysiology of enterotoxin-elicited diarrhea.