Institut Curie, PSL Research University, Endocytic Trafficking and Therapeutic Delivery group, 26 rue d'Ulm, 75248 Paris Cedex 05, France.
CNRS UMR3666, 75005 Paris, France.
Nat Cell Biol. 2016 Jan;18(1):54-64. doi: 10.1038/ncb3287. Epub 2015 Dec 7.
Integrins have key functions in cell adhesion and migration. How integrins are dynamically relocalized to the leading edge in highly polarized migratory cells has remained unexplored. Here, we demonstrate that β1 integrin (known as PAT-3 in Caenorhabditis elegans), but not β3, is transported from the plasma membrane to the trans-Golgi network, to be resecreted in a polarized manner. This retrograde trafficking is restricted to the non-ligand-bound conformation of β1 integrin. Retrograde trafficking inhibition abrogates several β1-integrin-specific functions such as cell adhesion in early embryonic development of mice, and persistent cell migration in the developing posterior gonad arm of C. elegans. Our results establish a paradigm according to which retrograde trafficking, and not endosomal recycling, is the key driver for β1 integrin function in highly polarized cells. These data more generally suggest that the retrograde route is used to relocalize plasma membrane machinery from previous sites of function to the leading edge of migratory cells.
整合素在细胞黏附和迁移中具有关键功能。然而,高度极化的迁移细胞中整合素如何动态重新定位到前缘仍未被探索。在这里,我们证明β1 整合素(在秀丽隐杆线虫中称为 PAT-3)而不是β3 整合素,从质膜运输到反式高尔基体网络,以极化方式重新分泌。这种逆行运输仅限于非配体结合构象的β1 整合素。逆行运输抑制会破坏几种β1 整合素特异性功能,例如在小鼠早期胚胎发育中的细胞黏附和秀丽隐杆线虫发育中的后性腺臂中的持续细胞迁移。我们的结果建立了一个范例,根据该范例,逆行运输而不是内体再循环是β1 整合素在高度极化细胞中发挥功能的关键驱动因素。这些数据更普遍地表明,逆行途径被用于将质膜机制从先前的功能部位重新定位到迁移细胞的前缘。