Larjava H
Department of Periodontics, University of Alabama School of Dentistry, Birmingham.
Am J Med Sci. 1991 Jan;301(1):63-8. doi: 10.1097/00000441-199101000-00012.
The majority of cell adhesive events to the extracellular matrix are mediated by cell surface receptors, beta 1 integrins. Keratinocytes express at least six different polypeptides of beta 1 integrin class, namely beta 1, alpha 2, alpha 3, alpha 5, and alpha 6 (alpha 6 is mainly associated with beta 4 polypeptide). These epithelial cells use alpha 2 beta 1 as a collagen receptor and alpha 3 beta 1 as a fibronectin receptor, while alpha 6 beta 4 is the major basement membrane receptor. Expression of alpha 5 beta 1 complex is low. Processing of beta 1 integrins is fast in keratinocytes; half-maximal maturation takes only 3 hours. In addition to their function in cell-matrix interactions, beta 1 integrins (alpha 2 beta 1 and alpha 3 beta 1) have also a role in maintaining keratinocyte cell-cell interactions. It is possible that resting basal keratinocytes use beta 1 integrins as cell-cell adhesion receptors, and during activation, like in wound healing, these receptors relocalize to mediate events involving cell-matrix interactions.
大多数细胞与细胞外基质的黏附事件是由细胞表面受体β1整合素介导的。角质形成细胞表达至少六种不同的β1整合素类多肽，即β1、α2、α3、α5和α6（α6主要与β4多肽相关）。这些上皮细胞将α2β1用作胶原蛋白受体，α3β1用作纤连蛋白受体，而α6β4是主要的基底膜受体。α5β1复合物的表达较低。β1整合素在角质形成细胞中的加工速度很快；达到最大成熟度一半仅需3小时。除了在细胞与基质相互作用中的功能外，β1整合素（α2β1和α3β1）在维持角质形成细胞间的相互作用中也起作用。静止的基底角质形成细胞有可能将β1整合素用作细胞间黏附受体，而在激活过程中，如在伤口愈合时，这些受体重新定位以介导涉及细胞与基质相互作用的事件。
