Yamada A, Yamaga T, Sakakibara H, Nakayama H, Oiwa K
Kansai Advanced Research Center, Communications Research Laboratory, Kobe, Japan.
J Cell Sci. 1998 Jan;111 ( Pt 1):93-8. doi: 10.1242/jcs.111.1.93.
Tetramethylrhodamine-labelled microtubules were observed to move on rows of dynein arms of sea urchin sperm axonemes exposed by elastase-induced sliding disintegration. The microtubules moved towards the flagellar tip at a velocity of 3.1+/-2.1 microm second-1 (mean +/- s.d., n=53) in the presence of 0.1 mM ATP at 22 degrees C, but none moved towards the sperm head. We also examined the polarity of microtubule binding to axonemal doublet microtubules in the absence of ATP by using microtubules brightly labelled at their minus-ends. In 140 of 210 microtubules studied, they bound to axonemal microtubules with a parallel polarity. These results suggest that tightly packed dynein arms on the outer doublet microtubules of sperm axoneme preferentially bind microtubules to themselves with the same polarity as that of the axoneme and that they generate a force to move only these microtubules in the direction away from the sperm head.
观察到用弹性蛋白酶诱导滑动解体后暴露的海胆精子轴丝的动力蛋白臂排上，四甲基罗丹明标记的微管在移动。在22℃下，存在0.1 mM ATP时，微管以3.1±2.1微米每秒的速度向鞭毛尖端移动（平均值±标准差，n = 53），但没有微管向精子头部移动。我们还通过使用在其负端明亮标记的微管，在没有ATP的情况下检查了微管与轴丝双联体微管结合的极性。在研究的210根微管中的140根中，它们以平行极性与轴丝微管结合。这些结果表明，精子轴丝外双联体微管上紧密排列的动力蛋白臂优先以与轴丝相同的极性将微管自身结合，并产生仅使这些微管向远离精子头部的方向移动的力。
