Eshel D, Shingyoji C, Yoshimura K, Gibbons B H, Gibbons I R, Takahashi K
Pacific Biomedical Research Center, University of Hawaii, Honolulu 96822.
J Exp Biol. 1990 Sep;152:441-51. doi: 10.1242/jeb.152.1.441.
Within the approximate range of 30-80 Hz, the flagellar beat frequency of a sea urchin sperm held by its head in the tip of a micropipet is governed by the vibration frequency of the micropipet. We have imposed abrupt changes in flagellar beat frequency by changing the vibration frequency of the micropipet within this range and used a high-speed video system to analyze the flagellar wave parameters during the first few cycles following the change. Our results demonstrate that the various flagellar beat parameters differ in the time they take to adjust to the new conditions. The initiation rate of new bends at the base is directly governed by the frequency of the vibration and changes immediately to the new frequency. The length and the propagation velocity of the developed bends become adjusted to the new conditions within approximately 1 beat cycle, whereas the bend angles take more than 4 beat cycles to attain their new steady-state value. Bends initiated shortly before the change in frequency occurs attain a final length and angle that depends on the relative durations of growth at the old and new frequencies. Our results suggest that the flagellar wavelength and bend angle are regulated by different mechanisms with the second not being directly dependent on bend initiation.
在大约30 - 80赫兹的范围内，用微吸管尖端夹住头部的海胆精子的鞭毛摆动频率受微吸管振动频率的控制。我们通过在此范围内改变微吸管的振动频率来突然改变鞭毛摆动频率，并使用高速视频系统分析变化后的最初几个周期内的鞭毛波形参数。我们的结果表明，各种鞭毛摆动参数在适应新条件所需的时间上有所不同。基部新弯曲的起始速率直接受振动频率的控制，并立即变为新频率。已形成弯曲的长度和传播速度在大约1个摆动周期内适应新条件，而弯曲角度则需要超过4个摆动周期才能达到其新的稳态值。在频率变化前不久开始的弯曲达到的最终长度和角度取决于在旧频率和新频率下生长的相对持续时间。我们的结果表明，鞭毛波长和弯曲角度受不同机制调节，其中弯曲角度并不直接依赖于弯曲起始。
