Direction of force generated by the inner row of dynein arms on flagellar microtubules.
Direction of force generated by the inner row of dynein arms on flagellar microtubules.
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DOI：
10.1083/jcb.105.4.1781
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发表时间：
1987-10
期刊：
影响因子：
--
通讯作者：
Sale WS
中科院分区：
文献类型：
--
作者：
Fox LA;Sale WS
我们的目标是确定鞭毛轴丝中内部动力蛋白臂产生力的方向。我们开发了一种有效的手段，提取外排的动力蛋白武器在脱膜精子尾部轴丝，离开内排的动力蛋白武器的结构和功能完整。精子尾轴丝耗尽外臂拍在一半的精子尾完整的武器在很宽的ATP浓度范围内的节拍频率。在ATP和胰蛋白酶的存在下，诱导分离的外臂耗尽的轴丝进行微管滑动。微管滑动的相对方向的电子显微镜分析（参见销售，W. S.和P. Satir，1977，Proc. Natl. Acad. Sci. USA，74：2045-2049）揭示了具有一排内部动力蛋白臂的双联体微管，双联体N，总是通过相对于双联体N + 1向轴丝的近端滑动而移动。因此，内臂产生力，使得双合透镜N将双合透镜N + 1推向尖端。这与在具有内外动力蛋白臂的轴丝中由ATP和胰蛋白酶诱导的微管滑动的方向相同。这一结果的影响，纤毛弯曲的机制和实用程序的功能定义的细胞质动力蛋白进行了讨论。
Our goal was to determine the direction of force generation of the inner dynein arms in flagellar axonemes. We developed an efficient means of extracting the outer row of dynein arms in demembranated sperm tail axonemes, leaving the inner row of dynein arms structurally and functionally intact. Sperm tail axonemes depleted of outer arms beat at half the beat frequency of sperm tails with intact arms over a wide range of ATP concentrations. The isolated, outer arm-depleted axonemes were induced to undergo microtubule sliding in the presence of ATP and trypsin. Electron microscopic analysis of the relative direction of microtubule sliding (see Sale, W. S. and P. Satir, 1977, Proc. Natl. Acad. Sci. USA, 74:2045-2049) revealed that the doublet microtubule with the row of inner dynein arms, doublet N, always moved by sliding toward the proximal end of the axoneme relative to doublet N + 1. Therefore, the inner arms generate force such that doublet N pushes doublet N + 1 tipward. This is the same direction of microtubule sliding induced by ATP and trypsin in axonemes having both inner and outer dynein arms. The implications of this result for the mechanism of ciliary bending and utility in functional definition of cytoplasmic dyneins are discussed.