Gossrau R
Institute of Anatomy, University Clinic Benjamin Franklin, Free University of Berlin, Germany.
Acta Histochem. 1998 Feb;100(1):99-112. doi: 10.1016/S0065-1281(98)80009-3.
Recently, it has been shown for mouse skeletal muscle that caveolin-3 is localized in the sarcolemma and cofractionates with the original dystrophin complex (DC). In order to find out whether caveolin-3 is a further component of the recently established and enlarged nitric oxide synthase (NOS) I-DC and whether members of this complex interact with and are potentially regulated by caveolin-3, mammalian and non-mammalian healthy and diseased (dystrophic) skeletal muscles were investigated using caveolin-3, NOS I, DC components and myosin immunohistochemistry as well as NOS I-associated diaphorase histochemistry. In healthy mammalian skeletal muscle, caveolin-3 was colocalized with the DC components in all extra- and intrafusal fibers. By contrast, NOS I was absent in type I extrafusal fibers of certain species. In patients with Duchenne muscular dystrophy and mdx mice the components of the NOS I-DC were not detected in all extra- and intrafusal fiber types, while caveolin-3 was found unchanged. In healthy non-mammalian skeletal muscle, i.e. of birds, reptiles and fishes, caveolin-3 immunoreactivity was lacking in the sarcolemma as was alpha-sarcoglycan; the other NOS I-DC components were either present or absent. In conclusion, although caveolin-3 is localized in the sarcolemma of mammalian myofibers, there are differences in the microarchitecture of the components of the DC complex and of caveolin-3 which does not appear to be linked with the NOS I-DC. Potential regulatory interactions between caveolin-3 and NOS I may nevertheless exist in those fibers where both molecules are colocalized. The absence of caveolin-3 and alpha-sarcoglycan immunoreactivities in non-mammalian myofibers may suggest that the functions of these proteins are subserved by other components of NOS I-DC complex.
最近的研究表明，在小鼠骨骼肌中，小窝蛋白-3定位于肌膜，并与原始的肌营养不良蛋白复合物（DC）共分级分离。为了弄清楚小窝蛋白-3是否是最近建立并扩大的一氧化氮合酶（NOS）I-DC的另一个组成部分，以及该复合物的成员是否与小窝蛋白-3相互作用并可能受其调节，我们使用小窝蛋白-3、NOS I、DC成分和肌球蛋白免疫组织化学以及与NOS I相关的黄递酶组织化学，对哺乳动物和非哺乳动物的健康及患病（营养不良）骨骼肌进行了研究。在健康的哺乳动物骨骼肌中，小窝蛋白-3在所有梭外和梭内纤维中均与DC成分共定位。相比之下，某些物种的I型梭外纤维中不存在NOS I。在杜兴氏肌营养不良症患者和mdx小鼠中，并非在所有梭外和梭内纤维类型中都能检测到NOS I-DC的成分，而小窝蛋白-3则未发生变化。在健康的非哺乳动物骨骼肌，即鸟类、爬行动物和鱼类的骨骼肌中，肌膜中缺乏小窝蛋白-3免疫反应性，α-肌聚糖也是如此；其他NOS I-DC成分有的存在，有的不存在。总之，尽管小窝蛋白-3定位于哺乳动物肌纤维的肌膜，但DC复合物和小窝蛋白-3的成分在微观结构上存在差异，且小窝蛋白-3似乎与NOS I-DC没有联系。不过，在这两种分子共定位的纤维中，小窝蛋白-3和NOS I之间可能存在潜在的调节相互作用。非哺乳动物肌纤维中缺乏小窝蛋白-3和α-肌聚糖免疫反应性，这可能表明这些蛋白质的功能由NOS I-DC复合物的其他成分承担。
