Circadian gene transcription plays a role in cellular metabolism in hibernating brown bears, Ursus arctos
Circadian gene transcription plays a role in cellular metabolism in hibernating brown bears, Ursus arctos
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DOI：
10.1007/s00360-023-01513-5
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发表时间：
2023-10-11
影响因子：
2
通讯作者：
Jansen，Heiko T.
中科院分区：
文献类型：
--
作者：
Vincent，Ellery P.;Perry，Blair W.;Jansen，Heiko T.
冬眠是一种高度季节性的生理适应，使棕熊（Ursus arctos）能够在长时间的低食物供应中生存下来。类似地，日常或昼夜节律通过协调身体过程以最佳地匹配环境光/暗周期来保存能量。棕熊在体内表达昼夜节律，它们的细胞在体外全年都表达昼夜节律，这表明这些节律可能在负能量平衡期间发挥重要作用。在这里，我们使用时间序列分析的RNA测序数据和定时测量脂肪来源的成纤维细胞在两个温度条件下，从活跃和冬眠季节的ATP生产，以确认存在的节奏。与冬眠体温（34 °C）相匹配的培养温度导致与活跃季节体温（37 °C）相比每日ATP产生峰值的延迟。线粒体基因转录峰值的时间发生了改变，电子传递链酶编码转录本的振幅也发生了改变。此外，我们观察到与昼夜节律系统和能量平衡相关的关键代谢基因（如SIRT 1和AMPK）的平均表达和时间发生变化。几个昼夜节律基因转录的幅度也降低了。这些结果揭示了冬眠中能量守恒和昼夜节律系统之间的联系。
Hibernation is a highly seasonal physiological adaptation that allows brown bears (Ursus arctos) to survive extended periods of low food availability. Similarly, daily or circadian rhythms conserve energy by coordinating body processes to optimally match the environmental light/dark cycle. Brown bears express circadian rhythms in vivo and their cells do in vitro throughout the year, suggesting that these rhythms may play important roles during periods of negative energy balance. Here, we use time-series analysis of RNA sequencing data and timed measurements of ATP production in adipose-derived fibroblasts from active and hibernation seasons under two temperature conditions to confirm that rhythmicity was present. Culture temperature matching that of hibernation body temperature (34 °C) resulted in a delay of daily peak ATP production in comparison with active season body temperatures (37 °C). The timing of peaks of mitochondrial gene transcription was altered as were the amplitudes of transcripts coding for enzymes of the electron transport chain. Additionally, we observed changes in mean expression and timing of key metabolic genes such asSIRT1andAMPKwhich are linked to the circadian system and energy balance. The amplitudes of several circadian gene transcripts were also reduced. These results reveal a link between energy conservation and a functioning circadian system in hibernation.