Membrane crystals of Ca2+-ATPase in sarcoplasmic reticulum of fast and slow skeletal and cardiac muscles.
Membrane crystals of Ca2+-ATPase in sarcoplasmic reticulum of fast and slow skeletal and cardiac muscles.
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快、慢骨骼肌和心肌肌浆网中 Ca2-ATP 酶的膜晶体。
DOI：
10.1111/j.1432-1033.1984.tb08154.x
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发表时间：
1984
期刊：
影响因子：
--
通讯作者：
Martonosi,A
中科院分区：
文献类型：
--
作者：
Dux,L;Martonosi,A
在无钙培养基中用Na 3VO 4处理后，在肌浆网膜中形成Ca 2+转运ATP酶的晶体阵列[Dux，L.和Martonosi，A.（1983）J.Biol.Chem.258，2599-2603）。从不同纤维类型（半膜肌、提肛肌、趾长伸肌、膈肌、比目鱼肌和心脏）的大鼠肌肉中分离的微粒体制备物中含有Ca 2 +-ATP酶晶体的囊泡比例与Ca 2 +-ATP酶含量和Ca 2 +-调节的ATP酶活性密切相关。这意味着在快速和慢速骨骼肌或心肌的肌浆网膜中Ca 2 +-ATP酶的浓度。两者仅略有不同，从慢收缩骨骼肌和心肌中分离的“肌浆网”制剂的低Ca 2+转运活性是由于存在大量的非肌浆网膜元件。这与通过冷冻蚀刻电子显微镜在红色和白色肌肉的肌浆网中观察到的8.5 nm膜内颗粒密度的相对较小差异雅阁。在不同纤维类型的肌浆网膜中，Ca 2 +-ATP酶晶格的尺寸是相似的;因此，如果Ca 2 +-ATP酶的“同工酶”之间存在结构差异，则这些差异不会反映在晶格中。
Crystalline arrays of Ca2+transport ATPase develop in sarcoplasmic reticulum membranes after treatment with Na3VO4in a calcium‐free medium [Dux, L. and Martonosi, A. (1983)J. Biol. Chem. 258, 2599–2603). The proportion of vesicles containing Ca2+‐ATPase crystals in microsome preparations isolated from rat muscle of different fiber types (semimembranosus, levator ani, extensor digitorum longus, diaphragm, soleus, and heart) correlates well with the Ca2+‐ATPase content and Ca2+‐modulated ATPase activity. This implies that the concentration of Ca2+‐ATPase in sarcoplasmic reticulum membranes of fast and slow skeletal or cardiac muscles. differs only slightly, and the low Ca2+transport activity of ‘sarcoplasmic reticulum’ preparations isolated from slow‐twitch skeletal and cardiac muscles is due to the presence of large amount of non‐sarcoplasmic‐reticulum membrane elements. This is in accord with the relatively small differences in the density of 8.5‐nm intramembranous particles seen by freeze‐etch electron microscopy in sarcoplasmic reticulum of red and white muscles. The dimensions of the Ca2+‐ATPase crystal lattice are similar in sarcoplasmic reticulum membranes of different fiber types; therefore if structural differences exist between ‘isoenzymes’ of Ca2+‐ATPase, these are not reflected in the crystal‐lattice.