Department of Neurobiology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, Massachusetts 01605, USA.
Nat Commun. 2012 Jul 17;3:958. doi: 10.1038/ncomms1965.
To navigate during their long-distance migration, monarch butterflies (Danaus plexippus) use a time-compensated sun compass. The sun compass timing elements reside in light-entrained circadian clocks in the antennae. Here we show that either antenna is sufficient for proper time compensation. However, migrants with either antenna painted black (to block light entrainment) and the other painted clear (to permit light entrainment) display disoriented group flight. Remarkably, when the black-painted antenna is removed, re-flown migrants with a single, clear-painted antenna exhibit proper orientation behaviour. Molecular correlates of clock function reveal that period and timeless expression is highly rhythmic in brains and clear-painted antennae, while rhythmic clock gene expression is disrupted in black-painted antennae. Our work shows that clock outputs from each antenna are processed and integrated together in the monarch time-compensated sun compass circuit. This dual timing system is a novel example of the regulation of a brain-driven behaviour by paired organs.
为了在长途迁徙中导航，黑脉金斑蝶（Danaus plexippus）使用时间补偿的太阳罗盘。太阳罗盘的定时元件位于触角中受光驱动的昼夜节律钟内。在这里，我们表明，每个触角都足以进行正确的时间补偿。然而，触角被涂成黑色（以阻止光摄入）和另一个触角涂成透明（以允许光摄入）的迁徙者表现出迷失方向的群体飞行。值得注意的是，当黑色触角被移除后，重新飞行的具有单个透明触角的迁徙者表现出正确的定向行为。与时钟功能相关的分子表明，在大脑和透明触角中，周期和无时间的表达具有高度的节律性，而在黑色触角中，节律性时钟基因的表达被打乱。我们的工作表明，来自每个触角的时钟输出在黑脉金斑蝶的时间补偿太阳罗盘电路中被一起处理和整合。这种双定时系统是由成对的器官调节大脑驱动行为的一个新例子。
