Graduate School of Science, Osaka City University, Sumiyoshi, Osaka 558-8585, Japan.
Biol Lett. 2012 Aug 23;8(4):488-91. doi: 10.1098/rsbl.2012.0079. Epub 2012 Mar 7.
The clock mechanism for circatidal rhythm has long been controversial, and its molecular basis is completely unknown. The mangrove cricket, Apteronemobius asahinai, shows two rhythms simultaneously in its locomotor activity: a circatidal rhythm producing active and inactive phases as well as a circadian rhythm modifying the activity intensity of circatidal active phases. The role of the clock gene period (per), one of the key components of the circadian clock in insects, was investigated in the circadian and circatidal rhythms of A. asahinai using RNAi. After injection of double-stranded RNA of per, most crickets did not show the circadian modulation of activity but the circatidal rhythm persisted without a significant difference in the period from controls. Thus, per is functionally involved in the circadian rhythm but plays no role, or a less important role, in the circatidal rhythm. We conclude that the circatidal rhythm in A. asahinai is controlled by a circatidal clock whose molecular mechanism is different from that of the circadian clock.
关于潮汐节律的时钟机制一直存在争议，其分子基础尚完全未知。招潮蟹表现出两种节律：一种是产生活动相和不活动相的潮汐节律，另一种是调制潮汐活动相活动强度的昼夜节律。本研究利用 RNAi 技术研究了昆虫昼夜节律钟关键组成部分之一的周期基因（per）在招潮蟹的昼夜节律和潮汐节律中的作用。注射 per 的双链 RNA 后，大多数蟋蟀没有表现出活动的昼夜调制，但潮汐节律仍然存在，与对照相比，周期没有明显差异。因此，per 参与昼夜节律的功能，但在潮汐节律中不起作用，或者作用较小。我们的结论是，招潮蟹的潮汐节律受潮汐钟控制，其分子机制不同于昼夜钟。
