von der Mark K, Ocalan M
Max-Planck-Gesellschaft, Universität Erlangen-Nürnberg, Federal Republic of Germany.
Differentiation. 1989 May;40(2):150-7. doi: 10.1111/j.1432-0436.1989.tb00823.x.
Skeletal myoblasts from fetal muscle respond adversely to fibronectin and laminin substrata: when primary mouse skeletal myoblasts are plated onto laminin, more myosin and desmin-positive myoblasts (myo+ cells) develop than on plates coated with fibronectin or collagen. In clonal cultures virtually all cells differentiate into postmitotic, fusion-capable myo + myoblasts on laminin after 3 days. In contrast, on fibronectin, the majority of the cells becomes myosin- and desmin-negative, partially due to proliferation of undifferentiated myoblast precursor cells, partially due to dedifferentiation or modulation of myoblasts into fibroblast-like myo- cells. Loss of the myogenic phenotype on fibronectin was also observed in cloned mouse myoblasts and in cultures of a differentiating mouse satellite cell line, MM14Dy, confirming that the appearance of desmin-negative cells is a result of myoblast modulation and not due simply to overgrowth by muscle fibroblasts. In the light of other effects of laminin on myoblasts, such as the stimulation of migration, differentiation and proliferation, our findings are consistent with the notion that laminin and fibronectin may be counteracting factors in the control of muscle differentiation.
当原代小鼠骨骼肌成肌细胞接种到层粘连蛋白上时，与接种在纤连蛋白或胶原蛋白包被的平板上相比，会产生更多肌球蛋白和结蛋白阳性的成肌细胞（肌阳性细胞）。在克隆培养中，实际上所有细胞在接种到层粘连蛋白上3天后都会分化为有丝分裂后、具有融合能力的肌阳性成肌细胞。相比之下，在纤连蛋白上，大多数细胞会变成肌球蛋白和结蛋白阴性，部分原因是未分化的成肌细胞前体细胞的增殖，部分原因是成肌细胞去分化或转变为成纤维细胞样的肌阴性细胞。在克隆的小鼠成肌细胞以及分化中的小鼠卫星细胞系MM14Dy的培养物中，也观察到纤连蛋白上肌源性表型的丧失，这证实结蛋白阴性细胞的出现是成肌细胞调节的结果，而不仅仅是由于肌肉成纤维细胞过度生长所致。鉴于层粘连蛋白对成肌细胞的其他作用，如刺激迁移、分化和增殖，我们的研究结果与层粘连蛋白和纤连蛋白可能是肌肉分化控制中的拮抗因子这一观点一致。
