Determination of the alpha-actinin-binding site on actin filaments by cryoelectron microscopy and image analysis.
Determination of the alpha-actinin-binding site on actin filaments by cryoelectron microscopy and image analysis.
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DOI：
10.1083/jcb.126.2.433
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发表时间：
1994-07
期刊：
影响因子：
--
通讯作者：
DeRosier D
中科院分区：
文献类型：
--
作者：
McGough A;Way M;DeRosier D
用鸡平滑肌α-辅肌动蛋白（α A1-2）的肌动蛋白结合结构域装饰的肌动蛋白丝的三维结构已被确定为21-A分辨率。α A1-2的形状和位置通过从装饰的细丝的重建中减去F-肌动蛋白的图来确定。α A1-2类似于一个钟，在其底部测量大约38 A，从其底部到其尖端延伸42 A。在装饰丝中，α A1-2的基部以肌动蛋白亚结构域2的外表面为中心，并沿长螺距（双头）螺旋链沿着接触两个相邻单体的亚结构域1。使用F-肌动蛋白的原子模型（Lorenz，M.，D. Popp和K. C.福尔摩斯1993. J. Mol. 234：826-836），我们已经能够直接测试特定肌动蛋白残基与α A1-2相互作用的可能性，这些特定肌动蛋白残基先前已被其他人鉴定。我们的研究结果表明，残基86-117和350-375包含不同的结合位点的α-辅肌动蛋白相邻的肌动蛋白单体。
The three-dimensional structure of actin filaments decorated with the actin-binding domain of chick smooth muscle alpha-actinin (alpha A1-2) has been determined to 21-A resolution. The shape and location of alpha A1-2 was determined by subtracting maps of F-actin from the reconstruction of decorated filaments. alpha A1-2 resembles a bell that measures approximately 38 A at its base and extends 42 A from its base to its tip. In decorated filaments, the base of alpha A1-2 is centered about the outer face of subdomain 2 of actin and contacts subdomain 1 of two neighboring monomers along the long-pitch (two-start) helical strands. Using the atomic model of F-actin (Lorenz, M., D. Popp, and K. C. Holmes. 1993. J. Mol. Biol. 234:826-836.), we have been able to test directly the likelihood that specific actin residues, which have been previously identified by others, interact with alpha A1-2. Our results indicate that residues 86-117 and 350-375 comprise distinct binding sites for alpha-actinin on adjacent actin monomers.