Intracellular MLCK1 diversion reverses barrier loss to restore mucosal homeostasis
Intracellular MLCK1 diversion reverses barrier loss to restore mucosal homeostasis
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DOI：
10.1038/s41591-019-0393-7
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发表时间：
2019-04-01
期刊：
影响因子：
82.9
通讯作者：
Turner, Jerrold R.
中科院分区：
文献类型：
--
作者：
Graham, W. Vallen;He, Weiqi;Turner, Jerrold R.
上皮屏障丧失是肠道和全身性疾病的驱动因素。肌球蛋白轻链激酶（MLCK）是屏障功能障碍的关键效应子和潜在的治疗靶点，但酶抑制剂具有不可接受的毒性。在这里，我们表明，一个独特的结构域内的MLCK剪接变异MLCK1指导连接周围肌动球蛋白环（PAMR）招聘。利用结构域结构和多重筛选，我们鉴定出一种结构域结合小分子（divertin），它可以阻断MLCK 1募集而不抑制酶功能。在体外和体内，戴维汀阻断急性肿瘤坏死因子（TNF）诱导的MLCK 1募集以及下游肌球蛋白轻链（MLC）磷酸化、屏障丧失和腹泻。在实验性炎症性肠病中，转向素纠正屏障功能障碍并预防疾病发展和进展。除了在胃肠道疾病中的应用之外，这种通过阻止进入特定亚细胞位点来抑制酶的一般方法为安全和精确地靶向具有多种功能的酶的个体特性提供了新的范例。
Epithelial barrier loss is a driver of intestinal and systemic diseases. Myosin light chain kinase (MLCK) is a key effector of barrier dysfunction and a potential therapeutic target, but enzymatic inhibition has unacceptable toxicity. Here, we show that a unique domain within the MLCK splice variant MLCK1 directs perijunctional actomyosin ring (PAMR) recruitment. Using the domain structure and multiple screens, we identify a domain-binding small molecule (divertin) that blocks MLCK1 recruitment without inhibiting enzymatic function. Divertin blocks acute, tumor necrosis factor (TNF)-induced MLCK1 recruitment as well as downstream myosin light chain (MLC) phosphorylation, barrier loss, and diarrhea in vitro and in vivo. Divertin corrects barrier dysfunction and prevents disease development and progression in experimental inflammatory bowel disease. Beyond applications of divertin in gastrointestinal disease, this general approach to enzymatic inhibition by preventing access to specific subcellular sites provides a new paradigm for safely and precisely targeting individual properties of enzymes with multiple functions.