Belkin A M, Stepp M A
Department of Biochemistry, The Holland Laboratory, American Red Cross, Rockville, Maryland 20855, USA.
Microsc Res Tech. 2000 Nov 1;51(3):280-301. doi: 10.1002/1097-0029(20001101)51:3<280::AID-JEMT7>3.0.CO;2-O.
Laminins are a family of trimeric glycoproteins present in the extracellular matrix and the major constituents of basement membranes. Integrins are alpha beta transmembrane receptors that play critical roles in both cell-matrix and cell-cell adhesion. Several members of the integrin family, including alpha 1 beta 1, alpha 2 beta 1, alpha 3 beta 1, alpha 6 beta 1, alpha 7 beta 1 and alpha 6 beta 4 heterodimers serve as laminin receptors on a variety of cell types. This review summarizes recent advances in understanding the involvement of individual integrins in cell interactions with laminins and the roles of laminin-binding integrins in adhesion-mediated events in vertebrates, including embryonic development, cell migration and tumor cell invasiveness, cell proliferation and differentiation, as well as basement membrane assembly. We discuss the regulation of integrin function via alternative splicing of cytoplasmic domains of alpha and beta subunits of the integrin receptors for laminins and present examples of functional collaboration between laminin-binding integrins and non-integrin laminin receptors. Advances in our understanding of the laminin-binding integrins continue to demonstrate the essential roles these receptors play in maintaining cell polarity and tissue architecture.
层粘连蛋白是存在于细胞外基质中的三聚体糖蛋白家族，也是基底膜的主要成分。整合素是αβ跨膜受体，在细胞与基质以及细胞与细胞的黏附中发挥关键作用。整合素家族的几个成员，包括α1β1、α2β1、α3β1、α6β1、α7β1和α6β4异二聚体，在多种细胞类型上作为层粘连蛋白受体。本综述总结了在理解单个整合素参与细胞与层粘连蛋白相互作用方面的最新进展，以及层粘连蛋白结合整合素在脊椎动物黏附介导事件中的作用，包括胚胎发育、细胞迁移和肿瘤细胞侵袭性、细胞增殖和分化以及基底膜组装。我们讨论了通过层粘连蛋白整合素受体α和β亚基细胞质结构域的可变剪接对整合素功能的调节，并给出了层粘连蛋白结合整合素与非整合素层粘连蛋白受体之间功能协作的例子。我们对层粘连蛋白结合整合素理解的进展继续证明了这些受体在维持细胞极性和组织结构中所起的重要作用。
