Nucleotide-induced global conformational changes of flagellar dynein arms revealed by in situ analysis
Nucleotide-induced global conformational changes of flagellar dynein arms revealed by in situ analysis
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DOI：
10.1038/nsmb.1832
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发表时间：
2010-06-01
影响因子：
16.8
通讯作者：
Ishikawa, Takashi
中科院分区：
文献类型：
--
作者：
Movassagh, Tandis;Bui, Khanh Huy;Ishikawa, Takashi
外部和内部动力蛋白臂产生用于鞭毛/纤毛弯曲运动的力。虽然核苷酸诱导的结构变化的动力蛋白重链（ATP驱动的电机）在体外被证明，我们缺乏原位知识，排除了理解的弯曲机制。在这里，我们揭示了核苷酸诱导的全球结构变化的外部和内部动力蛋白武器的衣原体莱茵鞭毛虫在原位使用电子冷冻断层扫描。动力蛋白重链的ATP酶结构域向远端移动，并且N-末端尾部在产物释放期间急剧弯曲。这种运动可以驱动相邻的微管引起滑动运动。与体外结果相反，在核苷酸的存在下，外部动力蛋白臂作为载脂蛋白或核苷酸结合形式的簇原位共存。这意味着一个合作的开关，这可能与弯曲的机制。
Outer and inner dynein arms generate force for the flagellar/ciliary bending motion. Although nucleotide-induced structural change of dynein heavy chains (the ATP-driven motor) was proven in vitro, our lack of knowledge in situ has precluded an understanding of the bending mechanism. Here we reveal nucleotide-induced global structural changes of the outer and inner dynein arms of Chlamydomonas reinhardtii flagella in situ using electron cryotomography. The ATPase domains of the dynein heavy chains move toward the distal end, and the N-terminal tail bends sharply during product release. This motion could drive the adjacent microtubule to cause a sliding motion. In contrast to in vitro results, in the presence of nucleotides, outer dynein arms coexist as clusters of apo or nucleotide-bound forms in situ. This implies a cooperative switching, which may be related to the mechanism of bending.