Electrophoretic analysis of multiple forms of myosin in fast-twitch and slow-twitch muscles of the chick.
Electrophoretic analysis of multiple forms of myosin in fast-twitch and slow-twitch muscles of the chick.
复制标题
对雏鸡快肌和慢肌中多种形式的肌球蛋白进行电泳分析。
作者：
J. Hoh;P. A. McGrath;R. White
1.描述了一种在含有0.02 M-焦磷酸盐和10%（v/v）甘油，pH 8.8的缓冲体系中，在聚丙烯酰胺凝胶中电泳分析完整肌球蛋白的方法。2.在这个系统中，鸡背阔肌肌球蛋白揭示了五个不同的电泳组分，三个组件从快速收缩的背阔肌后，两个缓慢迁移的组件从缓慢收缩的背阔肌前。3.肌球蛋白组分的Ca 2+激活的ATP酶（腺苷三磷酸酶）活性通过对凝胶进行光密度扫描以测定在ATP酶反应期间形成的Ca 3（PO 4）2沉淀和随后的染色蛋白。来自同一肌肉的每种组分似乎具有相同的ATP酶活性，但来自快收缩肌肉的组分的活性比来自慢收缩肌肉的组分高2.2倍。4.在相同的缓冲液系统中重新电泳，个别馏分的快速收缩肌球蛋白没有再现的三带模式的原始肌球蛋白，但迁移率与他们原来的流动性一致。5.三个快速收缩肌球蛋白组分在不同浓度的凝胶中的流动性分析表明，它们彼此不是稳定的低聚物。6.提示快缩肌球蛋白和慢缩肌球蛋白是肌球蛋白的同工酶。
1. A method is described for the electrophoretic analysis of intact myosin in polyacrylamide gel in a buffer system containing 0.02 M-pyrophosphate and 10% (v/v) glycerol, pH 8.8. 2. In this system chicken skeletal-muscle myosins reveal five distinct electrophoretic components, three components from the fast-twitch posterior latissimus dorsi muscle and two slower-migrating components from the slow-twitch anterior latissimus dorsi muscle. 3. The Ca2+-activated ATPase (adenosine triphosphatase) activity of myosin components was measured by densitometric scanning of the gel for the Ca3(PO4)2 precipitate formed during the ATPase reaction and subsequently for stained protein. Each component from the same muscle appears to have identical ATPase activity, but components from the fast-twitch muscle had an activity 2.2 times higher than those from the slow-twitch muscle. 4. On re-electrophoresis in the same buffer system, individual fractions of fast-twitch myosin did not reproduce the three-band pattern of the original myosin, but migrated at rates consistent with their original mobility. 5. Analysis of the mobility of the three fast-twitch myosin components in gels of different concentrations suggests that they are not stable oligomers of each other. 6. It is suggested that these components of fast-twitch myosin and slow-twitch myosin are isoenzymes of myosin.