Abstract:
The tight junction is an important subcellular organelle which plays a vital role in epithelial barrier function. Claudin, as the integral membrane component of tight junctions, creates a paracellular transport pathway for various ions to be reabsorbed by the kidneys. This review summarizes advances in claudin structure, function and pathophysiology in kidney diseases. Different claudin species confer selective paracellular permeability to each of three major renal tubular segments: the proximal tubule, the thick ascending limb of Henle\'s loop and the distal nephron. Defects in claudin function can cause a wide spectrum of kidney diseases, such as hypomagnesemia, hypercalciuria, kidney stones and hypertension. Studies using transgenic mouse models with claudin mutations have recapitulated several of these renal disease phenotypes and have elucidated the underlying biological mechanisms. Modern recording approaches based upon scanning ion conductance microscopy may resolve the biophysical nature of claudin transport function and provide novel insight into tight junction architecture.
摘要:
紧密连接是重要的亚细胞细胞器,在上皮屏障功能中起着至关重要的作用。Claudin,作为紧密连接的整体膜组件,为肾脏重新吸收各种离子创造了细胞旁转运途径。这篇综述总结了claudin结构的进展,肾脏疾病的功能和病理生理学。不同的claudin物种赋予三个主要肾小管节段的选择性细胞旁通透性:近端小管,Henle'sloop和远端肾单位的粗上升肢。claudin功能缺陷可导致广泛的肾脏疾病,如低镁血症,高钙尿症,肾结石和高血压.使用具有claudin突变的转基因小鼠模型的研究已经概括了这些肾脏疾病表型中的几种,并阐明了潜在的生物学机制。基于扫描离子电导显微镜的现代记录方法可以解决claudin传输功能的生物物理性质,并提供对紧密连接结构的新颖见解。