Comparative biochemistry of non-muscle actins.
Comparative biochemistry of non-muscle actins.
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非肌肉肌动蛋白的比较生物化学。
DOI：
10.1016/s0021-9258(17)40971-9
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发表时间：
1977
期刊：
影响因子：
--
通讯作者：
K. Ed
中科院分区：
文献类型：
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作者：
Gordon Dj;J. Boyer;K. Ed
代表整个细胞库的肌动蛋白已经通过包括在DEAE-纤维素上层析的方法以25 - 30%的产率从鸡胚脑、人血小板、大鼠肝和卡氏棘阿米巴中分离出来（Gordon，DJ，Eisenberg，E.，和Korn，艾德（1976）生物化学杂志251，4778-4786）。脑、血小板和肝肌动蛋白含有p-和y-异肌动蛋白，先前已被其他人描述，其等电点比兔骨骼肌的肌动蛋白碱性更强。阿米巴肌动蛋白是一种比脊椎动物非肌肉细胞的γ-肌动蛋白碱性更强的单一等电物种。如先前对于Acunthumoebu肌动蛋白所发现的（Gordon，DJ，Yang，Y. Z.，和Korn，E. D.（1976年）5. 251，7474-7479），脊椎动物非肌肉肌动蛋白的聚合性质也在定性上类似于兔骨骼肌肌动蛋白的聚合，但是，在定量上，非肌肉肌动蛋白尽管它们的来源非常不同，但它们彼此之间都比任何一种与肌肉肌动蛋白之间更相似。这些数据不同于胚胎鸡脑肌动蛋白仅在非常高的浓度下聚合以形成次结晶聚集体而不是细丝的报道（Bray，D.，和托马斯，C.等（1976）J. Mol. 105，527-544），并且人血小板含有与肌肉肌动蛋白不同地聚合的肌动蛋白（Abramowitz，JW，Stracher，A.，和Detwiler，T. C. 05.《生物化学与生物物理学文献》，1973年。167，230-237）。这三种v-脊椎动物非肌肉肌动蛋白在实验上是不可区分的，并且比Acanthumoehu肌动蛋白更像兔骨骼肌肌动蛋白，在它们激活兔肌肉重肌球蛋白MgZ+ ATP酶的能力方面，尽管没有一种非肌肉肌动蛋白像肌肉肌动蛋白那样有效。脑、血小板和Acunthumoebu的提取物含有单体G-肌动蛋白，其浓度远远大于纯化肌动蛋白的临界聚合浓度。因此，我们推断，存在其他因素与肌动蛋白相互作用，使其保持非聚合状态。在非肌肉细胞中，肌动蛋白的聚集状态可能受这些因子以及与聚合的F-肌动蛋白相互作用的其他因子的调节，而不依赖于非肌细胞。
Actin representative of the entire cell pool has been isolated in 25 to 30% yield from chick embryonic brain, human platelet, rat liver, and Acunthumoeba castellanii by a procedure involving chromatography on DEAE-cellulose (Gordon, DJ, Eisenberg, E., and Korn, ED (1976) J. Biol. Chem. 251, 4778-4786). Brain, platelet, and liver actins contain the p-and y-isoactins, previously described by others, with isoelectric points more alkaline than the aactin of rabbit skeletal muscle. Acanthamoeba actin is a single isoelectric species more alkaline than the y-actin of vertebrate non-muscle cells. As found previously for Acunthumoebu actin (Gordon, DJ, Yang, Y.-Z., and Korn, E. D.(1976) 5. Biol. Chem. 251, 7474-7479), the polymerization properties of the verbebrate non-muscle actins are also qualitatively similar to the polymerization of rabbit skeletal muscle actin, but, quantitatively, the non-muscle actins, despite their very different origins, are all much more similar to each other than any is to muscle actin. These data differ from reports that embryonic chick brain actin polymerizes only at very high concentrations to form paracrystalline aggregates rather than filaments(Bray, D., and Thomas, C.(1976) J. Mol. Biol. 105, 527-544) and that human platelets contain actin which polymerizes differently than muscle actin (Abramowitz, JW, Stracher, A., and Detwiler, T. C.(1973) Arch. Biochem. Biophys. 167, 230-237). The three v-ertebrate non-muscle actins were experimentally indistinguishable, and more like rabbit skeletal muscle actin than Acanthumoehu actin, in their ability to activate rabbit muscle heavy meromyosin MgZ+ ATPase although none of the non-muscle actins is as effective as muscle actin.Extracts of brain, platelets, and Acunthumoebu contain monomeric G-actin at concentrations much greater than the critical polymerization concentrations of the purified actins. We infer, therefore, the presence of other factors that interact with the actin to keep it nonpolymerized. The state of aggregation of actin in non-muscle cells is, presumably, regulated by such factors, and by others that interact with polymerized F-actin, and does not depend on non-