Dystrophin-glycoprotein complex is highly enriched in isolated skeletal muscle sarcolemma.
Dystrophin-glycoprotein complex is highly enriched in isolated skeletal muscle sarcolemma.
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DOI：
10.1083/jcb.112.1.135
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发表时间：
1991-01
影响因子：
7.8
通讯作者：
Campbell, K P
中科院分区：
文献类型：
--
作者：
Ohlendieck, K;Ervasti, J M;Snook, J B;Campbell, K P
特异性针对兔骨骼肌表面膜蛋白组分的mAb已被用作骨骼肌肌膜分离和表征的标记物。用麦胚凝集法从兔骨骼肌表面膜粗品中分离出高纯度的肌膜。从骨骼肌的亚细胞组分的免疫印迹分析表明，肌营养不良蛋白及其相关的糖蛋白的156和50 kD的大大丰富纯化的肌膜囊泡。纯化的肌膜还富含新的肌膜标记物（SL 45，SL/TS 230）和Na+/K（+）-ATP酶，而t-小管标记物（二氢吡啶受体的α 1和α 2亚基，TS 28）和肌浆网标记物（Ca 2（+）-ATP酶，ryanodine受体）在该制剂中大大减少。用SDS-PAGE和光密度扫描法对分离的肌膜进行分析，结果表明肌营养不良蛋白占肌膜总蛋白的2%。因此，我们的研究结果表明，虽然肌营养不良蛋白是一种次要的肌肉蛋白，它是骨骼肌肌膜的主要成分。因此，杜氏肌营养不良症中肌营养不良蛋白的缺失可能导致营养不良肌肉中肌膜下的细胞骨架网络的主要破坏。
mAbs specific for protein components of the surface membrane of rabbit skeletal muscle have been used as markers in the isolation and characterization of skeletal muscle sarcolemma membranes. Highly purified sarcolemma membranes from rabbit skeletal muscle were isolated from a crude surface membrane preparation by wheat germ agglutination. Immunoblot analysis of subcellular fractions from skeletal muscle revealed that dystrophin and its associated glycoproteins of 156 and 50 kD are greatly enriched in purified sarcolemma vesicles. The purified sarcolemma was also enriched in novel sarcolemma markers (SL45, SL/TS230) and Na+/K(+)-ATPase, whereas t-tubule markers (alpha 1 and alpha 2 subunits of dihydropyridine receptor, TS28) and sarcoplasmic reticulum markers (Ca2(+)-ATPase, ryanodine receptor) were greatly diminished in this preparation. Analysis of isolated sarcolemma by SDS- PAGE and densitometric scanning demonstrated that dystrophin made up 2% of the total protein in the rabbit sarcolemma preparation. Therefore, our results demonstrate that although dystrophin is a minor muscle protein it is a major constituent of the sarcolemma membrane in skeletal muscle. Thus the absence of dystrophin in Duchenne muscular dystrophy may result in a major disruption of the cytoskeletal network underlying the sarcolemma in dystrophic muscle.