Myosin isozyme distribution in rodent hindlimb skeletal muscle.
Myosin isozyme distribution in rodent hindlimb skeletal muscle.
复制标题
啮齿动物后肢骨骼肌中肌球蛋白同工酶的分布。
DOI：
10.1152/jappl.1986.60.6.1923
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
Herrick,RE
中科院分区：
文献类型：
--
作者：
Thomason,DB;Baldwin,KM;Herrick,RE
本研究的目的是检查肌球蛋白同工酶在啮齿动物（褐家鼠）后肢骨骼肌和已知具有对比纤维型组成的肌肉区域的分布。对肌肉样品进行Ca2+调节的肌原纤维腺苷三磷酸酶（ATPase）活性、Ca2+激活的肌球蛋白atp酶活性、肌球蛋白同工酶谱和肌球蛋白轻链谱分析。根据天然蛋白和轻链电泳图谱，鉴定出4种肌球蛋白同工酶：1种主要与慢肌（SM）相关，3种主要与快肌（FM）相关。对Ca2+调控的肌原纤维atp酶活性（pCA 4）与测定的同工酶谱进行多元线性回归分析，估计各同工酶的肌原纤维atp酶活性（FM1 = 0.86, FM2 = 0.52, FM3 = 0.31, SM = 0.15）。肌原纤维蛋白-1。min-1在25℃，n = 180， P小于0.001)。天然同工酶谱和肌原纤维atp酶活性在肌肉和类似纤维类型组成的肌肉区域之间的差异表明，特定纤维类型不一定表达单一同工酶谱。这些数据与假设一致，即在啮齿动物后肢骨骼肌及其固有的运动单元中，存在一系列肌球蛋白同工酶谱，可能提供广泛的机械表达。
The purpose of this study was to examine the distribution of myosin isozymes in rodent (Rattus norvegicus) hindlimb skeletal muscles and regions of muscle known to have contrasting fiber-type composition. Muscle samples were analyzed for Ca2+-regulated myofibril adenosine triphosphatase (ATPase) activity, Ca2+-activated myosin ATPase activity, myosin isozyme profile, and myosin light chain profile. Four isozymes of myosin were identified based on native protein and light chain electrophoresis patterns: one associated primarily with slow-twitch muscle (SM) and three associated primarily with fast-twitch muscle (FM). Multiple linear regression analysis of Ca2+-regulated myofibril ATPase activity (pCA 4) vs. measured isozyme profile was used to estimate the myofibril ATPase activities of the individual isozymes (FM1 = 0.86, FM2 = 0.52, FM3 = 0.31, and SM = 0.15 mumol Pi formed . mg myofibril protein-1 . min-1 at 25 degrees C, n = 180, P less than 0.001). Differences in the native isozyme profiles and myofibril ATPase activities between muscles and muscle regions of similar fiber type composition indicate that a given fiber type may not necessarily express a single isozyme profile. These data are consistent with the hypothesis that, among rodent hindlimb skeletal muscles and inherently their motor units, a range of myosin isozyme profiles exists that may provide a broad range of mechanical expression.