A separate circadian oscillator controls nocturnal migratory restlessness in the songbird Sylvia borin
A separate circadian oscillator controls nocturnal migratory restlessness in the songbird Sylvia borin
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DOI：
10.1177/0748730405281826
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发表时间：
2005-12-01
影响因子：
3.5
通讯作者：
Gwinner, E
中科院分区：
文献类型：
--
作者：
Bartell, PA;Gwinner, E
当被关在笼子里时，迁徙鸣禽在春季和秋季迁徙期间表现出夜间迁徙的不安（也称为Zugunruhe），尽管这些鸟类在一年中的剩余时间里只在白天活动。Zugunruhe，这已被证明是直接控制的一个circannual定时器，其特点是一个刻板的“翅膀呼呼”的行为，而鸟栖息。为了阐明昼夜节律系统在祖贡鲁和调节中所起的作用，作者研究了花园莺（Sylviaborin）在不同长度的骨架光周期和恒定的弱光下的活动。在11.5D：1L10.5D：1L的骨架光周期中，作者发现，祖贡鲁赫在相当大比例的鸟类中自由奔跑，而它们的正常日常活动（例如，饲养和梳理）保持同步至24小时。一些表达Zugunruhe的鸟类在恒定的昏暗光线下继续表现出两种不同的活动：一种对应于日常活动，另一种对应于翅膀呼呼作响。在某些情况下，这两个回合交叉，而自由运行与不同的时期。表达Zugunruhe的鸟类也比没有表达的鸟类有更长的自由奔跑时间。研究数据表明，Zugunruhe的季节性出现是至少2个昼夜振荡器相互作用的结果，这2个振荡器的相位关系决定了夜间迁徙不安的表达。此外，这些数据与先前提出的内部巧合假说作为个体发育的年周期节律的模型是一致的。
When confined to a cage, migratory songbirds exhibit nocturnal migratory restlessness (also called Zugunruhe) during the spring and autumn migratory periods, even though these birds are exclusively diurnal during the remainder of the year. Zugunruhe, which has been demonstrated to be under the direct control of a circannual timer, is characterized by a stereotypic "wing-whirring" behavior while the bird is perched. To elucidate the role played by the circadian system in the regulation of Zugunruhe, the authors studied the activity of garden warblers (Sylvia borin), long-distance nocturnal migrants, under skeleton photoperiods of different lengths and under constant dim light. In 11.5D:1L10.5D:1L skeleton photoperiods, the authors found that Zugunruhe free-ran in a substantial proportion of birds, while their normal daily activities (e.g., feeding and preening) remained synchronized to 24 h. Some birds expressing Zugunruhe under constant dim light continued to show 2 distinct bouts of activity: one corresponding to daily activities, the other to wing-whirring. In some cases, these 2 bouts crossed while free-running with different periods. Birds expressing Zugunruhe also had significantly longer free-running periods than birds that did not. The study data suggest that the seasonal appearance of Zugunruhe is the result of the interactions of at least 2 circadian oscillators and that it is the phase relationship of these 2 oscillators that determines when nocturnal migratory restlessness is expressed. Furthermore, these data are consistent with the previously proposed internal coincidence hypothesis as a model for the ontogeny of circannual rhythms.