Department of Nephrology, Children's Hospital of Pittsburgh, Pittsburgh, PA 15224, USA.
Pediatr Nephrol. 2013 Sep;28(9):1723-37. doi: 10.1007/s00467-012-2281-y. Epub 2012 Aug 30.
Podocytes are highly specialized epithelial cells localized in the kidney glomerulus. The distinct cell signaling events and unique cytoskeletal architecture tailor podocytes to withstand changes in hydrostatic pressure during glomerular filtration. Alteration of glomerular filtration leads to kidney disease and frequently manifests with proteinuria. It has been increasingly recognized that cell signaling and cytoskeletal dynamics are coupled more tightly to membrane trafficking than previously thought. Membrane trafficking coordinates the cross-talk between protein networks and signaling cascades in a spatially and temporally organized fashion and may be viewed as a communication highway between the cell exterior and interior. Membrane trafficking involves transport of cargo from the plasma membrane to the cell interior (i.e., endocytosis) followed by cargo trafficking to lysosomes for degradation or to the plasma membrane for recycling. Yet, recent studies indicate that the conventional classification does not fully reflect the complex and versatile nature of membrane trafficking. While the increasing complexity of elaborate protein scaffolds and signaling cascades is being recognized in podocytes, the role of membrane trafficking is less well understood. This review will focus on the role of membrane trafficking in podocyte health and disease.
足细胞是高度特化的上皮细胞，位于肾脏肾小球中。独特的细胞信号事件和细胞骨架结构使足细胞能够适应肾小球滤过过程中压力变化。肾小球滤过的改变会导致肾脏疾病，并经常表现为蛋白尿。人们越来越认识到，细胞信号和细胞骨架动力学与膜运输的联系比以前认为的更紧密。膜运输以空间和时间组织的方式协调蛋白质网络和信号级联之间的串扰，并可以看作是细胞内外通讯的高速公路。膜运输涉及将货物从质膜运输到细胞内部（即内吞作用），然后将货物运输到溶酶体进行降解或运送到质膜进行再循环。然而，最近的研究表明，传统的分类法不能完全反映膜运输的复杂和多样的性质。虽然在足细胞中越来越认识到精细的蛋白质支架和信号级联的日益复杂性，但膜运输的作用还不太清楚。这篇综述将重点介绍膜运输在足细胞健康和疾病中的作用。
