Yamada H, Chiba A, Endo T, Kobata A, Anderson L V, Hori H, Fukuta-Ohi H, Kanazawa I, Campbell K P, Shimizu T, Matsumura K
Department of Neurology and Neuroscience, Teikyo University School of Medicine, Tokyo, Japan.
J Neurochem. 1996 Apr;66(4):1518-24. doi: 10.1046/j.1471-4159.1996.66041518.x.
Dystoroglycan is encoded by a single gene and cleaved into two proteins, alpha and beta-dystroglycan, by posttranslational processing. The 120kDa peripheral nerve isoform of alpha-dystroglycan binds laminin-2 comprised of the alpha 2, beta 1, and gamma 1 chains. In congenital muscular dystrophy and dy mice deficient in laminin alpha 2 chain, peripheral myelination is disturbed, suggesting a role for the dystroglycan- laminin interaction in peripheral myelinogenesis. To begin to test this hypothesis, we have characterized the dystroglycan-laminin interaction in peripheral nerve. We demonstrate that (1) alpha-dystroglycan is an extracellular peripheral membrane glycoprotein that links beta-dystroglycan in the Schwann cell outer membrane with laminin-2 in the endoneurial basal lamina, and (2) dystrophin homologues Dp116 and utrophin are cytoskeletal proteins of the Schwann cell cytoplasm. We also present data that suggest a role for glycosylation of alpha-dystroglycan in the interaction with laminin.
肌营养不良聚糖由单个基因编码，并通过翻译后加工切割成两种蛋白质，即α-和β-肌营养不良聚糖。α-肌营养不良聚糖的120kDa外周神经异构体与由α2、β1和γ1链组成的层粘连蛋白-2结合。在先天性肌营养不良和层粘连蛋白α2链缺陷的dy小鼠中，外周髓鞘形成受到干扰，提示肌营养不良聚糖-层粘连蛋白相互作用在周围髓鞘形成中起作用。为了开始验证这一假设，我们对外周神经中肌营养不良聚糖-层粘连蛋白的相互作用进行了表征。我们证明：（1）α-肌营养不良聚糖是一种细胞外外周膜糖蛋白，它将雪旺细胞外膜中的β-肌营养不良聚糖与神经内膜基底膜中的层粘连蛋白-2连接起来；（2）肌营养不良蛋白同系物Dp116和肌营养蛋白是雪旺细胞胞质中的细胞骨架蛋白。我们还提供了数据，表明α-肌营养不良聚糖的糖基化在与层粘连蛋白的相互作用中起作用。
