Duband J L, Gimona M, Scatena M, Sartore S, Small J V
Laboratoire de Biologie Cellulaire du Developpement, Institut Jacques Monod, Universite Paris 7, France.
Differentiation. 1993 Dec;55(1):1-11. doi: 10.1111/j.1432-0436.1993.tb00027.x.
Calponin and SM 22 are two proteins related in sequence that are particularly abundant in smooth muscle cells. Here, the distribution patterns of calponin and SM 22 were compared with that of other smooth muscle contractile and cytoskeletal components in the avian embryo using immunofluorescence microscopy and immunoblotting. Like myosin-light-chain kinase and heavy caldesmon, both calponin and SM 22 were more or less exclusively found in smooth muscle cells, during embryonic development and in the adult. Labelling of other cell types including striated muscle was not observed. In contrast, tropomyosin, smooth muscle alpha-actin, filamin and desmin could also be detected in many other cell types in addition to smooth muscles, at least during part of embryonic life. Calponin and SM 22 appeared almost synchronously during the differentiation of all smooth muscle cell populations, though with a slight time difference in the case of the aorta. The appearance of calponin, SM 22 and heavy caldesmon was generally delayed in relation to desmin, tropomyosin, smooth muscle alpha-actin, myosin-light-chain kinase and filamin and a marked increase in abundance of these proteins was observed in the late embryo and in the adult. From these observations we can conclude that both calponin and SM 22 belong to a group of late differentiation determinants in smooth muscle and may constitute convenient and reliable markers to follow the differentiation of most, if not all, smooth muscle cell populations.
钙调蛋白和SM 22是两种序列相关的蛋白质，在平滑肌细胞中含量特别丰富。在此，利用免疫荧光显微镜和免疫印迹技术，比较了禽类胚胎中钙调蛋白和SM 22与其他平滑肌收缩和细胞骨架成分的分布模式。与肌球蛋白轻链激酶和重钙调蛋白类似，在胚胎发育期间及成年后，钙调蛋白和SM 22或多或少仅在平滑肌细胞中发现，未观察到包括横纹肌在内的其他细胞类型的标记。相反，至少在胚胎生命的部分阶段，除平滑肌外，在许多其他细胞类型中也可检测到原肌球蛋白、平滑肌α-肌动蛋白、细丝蛋白和结蛋白。在所有平滑肌细胞群体分化过程中，钙调蛋白和SM 22几乎同时出现，不过主动脉的情况存在轻微的时间差异。钙调蛋白、SM 22和重钙调蛋白的出现通常相对于结蛋白、原肌球蛋白、平滑肌α-肌动蛋白、肌球蛋白轻链激酶和细丝蛋白有所延迟，并且在胚胎后期和成年期观察到这些蛋白质的丰度显著增加。从这些观察结果我们可以得出结论，钙调蛋白和SM 22都属于平滑肌中的一组晚期分化决定因素，并且可能构成方便且可靠的标记物，用于追踪大多数（如果不是全部）平滑肌细胞群体的分化。
