Ogawa K
Department of Cell Biology, National Institute for Basic Biology, Okazaki, Japan.
Nature. 1991 Aug 15;352(6336):643-5. doi: 10.1038/352643a0.
The 'motor' proteins of eukaryotic cells contain specialized domains that hydrolyse ATP to produce force and movement along a cytoskeletal polymer (actin in the case of the myosin family; microtubules in the case of the kinesin family and dyneins). There are motor-protein superfamilies in which each member has a conserved force-generating domain joined to a different 'tail' which conveys specific attachment properties. The minus-end-directed microtubule motors, the dyneins, may also constitute a superfamily of force-generating proteins with distinct attachment domains. Axonemal outer-arm dynein from sea urchin spermatozoa is a multimeric protein consisting of two heavy chains (alpha and beta) with ATPase activity, three intermediate chains and several light chains. Here I report the sequence of cloned complementary DNA encoding the beta heavy chain of a dynein motor molecule. The predicted amino-acid sequence reveals four ATP-binding consensus sequences in the central domain. The dynein beta heavy chain is thought to associate transiently with a microtubule during ATP hydrolysis, but the ATP-dependent microtubule-binding sequence common to the kinesin superfamily is not found in the dynein beta heavy chain. These unique features distinguish the dynein beta heavy chain from other motor protein superfamilies and may be characteristic of the dynein superfamily.
真核细胞的“马达”蛋白含有特殊结构域，可水解三磷酸腺苷（ATP）以产生力并沿着细胞骨架聚合物移动（肌球蛋白家族作用于肌动蛋白；驱动蛋白家族和动力蛋白作用于微管）。存在马达蛋白超家族，其中每个成员都有一个保守的产生力的结构域，与一个不同的“尾部”相连，该“尾部”具有特定的附着特性。向微管负端移动的马达蛋白——动力蛋白，也可能构成一个具有不同附着结构域的产生力的蛋白质超家族。海胆精子的轴丝外臂动力蛋白是一种多聚体蛋白，由两条具有ATP酶活性的重链（α和β）、三条中间链和几条轻链组成。在此，我报告编码动力蛋白马达分子β重链的克隆互补DNA的序列。预测的氨基酸序列在中央结构域显示出四个ATP结合共有序列。动力蛋白β重链被认为在ATP水解过程中与微管短暂结合，但在动力蛋白β重链中未发现驱动蛋白超家族共有的依赖ATP的微管结合序列。这些独特特征使动力蛋白β重链区别于其他马达蛋白超家族，可能是动力蛋白超家族的特征。
