Many researchers found that there is a close connection between biological rhythm and metabolism in mammals and humans. But, it is uncertain whether there is a central and peripheral clock system in fish or not, and it is also uncertain whether there is a relationship between them. This article used the model fish, marine medaka (Oryzias melastigma) as the experimental object, and built a complete test with 2 factors and 2 levels, the photoperiod factor with Light (L): Dark (D) = 16:8 and 12:12 and the factor of feeding time with 1 h after light and 1 h before dark, to verify the existence of the clock system and explore the relationship between biological rhythm and metabolism. The results showed that: In treatment 1# with L:D = 16:8 and 1 h after light, two clock genes of Bmal1 and Per1, among the tested 6 clock genes, had obvious rhythmic expression in the brain and in the liver, and 2 metabolic genes of Elovl5 and Lpl also had obvious rhythmic oscillations in the liver. In treatment 2# with L:D = 12:12 and 1 h after light, 3 clock genes (Bmal1, Per1 and Per2) had obvious rhythmic expression in the brain and in the liver, and 5 metabolic genes (Elovl5, Lpl, Fadsd2, Tryp, Pck) also presented rhythmic oscillations in the liver. Both treatments had the same photoperiod, the treatment with feeding at 1 h before dark still had several clock genes in the brain that were rhythmical, but neither clock gene nor metabolic gene in the liver exhibited obvious rhythmic oscillations. This study showed that there were biological rhythms in marine medaka, and there was a close relationship between the biological rhythm and the lipid metabolism. According to the set 2 factors, it is found that the photoperiod could mainly affect the central clock system, and the feeding time could mainly affect the rhythmic expression of the peripheral clock and metabolic genes. The conclusion will provide a scientific and efficient breeding strategy for marine medaka.

中文翻译：

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海洋青鳉（Oryzias melastigma）生物钟和代谢基因的节律性表达

许多研究人员发现，哺乳动物和人类的生物节律与新陈代谢之间存在密切联系。但是，鱼体内是否存在中央时钟系统和外围时钟系统尚不确定，它们之间是否存在关系也不确定。本文使用模型鱼，海洋青鳉（Oryzias melastigma) 为实验对象，构建了一个完整的 2 因子 2 水平的测试，光照 (L): 黑暗 (D) = 16:8 和 12:12 的光周期因子和光照后 1 h 的投喂时间因子以及天黑前1小时，验证生物钟系统的存在，探索生物节律与新陈代谢的关系。结果表明：在L:D=16:8和光照后1 h处理1#中，被测6个时钟基因中，Bmal1和Per1两个时钟基因在脑和肝脏中均有明显的节律性表达， Elovl5和Lpl的2个代谢基因在肝脏也有明显的节律性振荡。在L:D = 12:12和光照后1 h的2#处理中，3个时钟基因（Bmal1、Per1和Per2）在大脑和肝脏中有明显的节律性表达，5个代谢基因（Elovl5、Lpl、Fadsd2） , 胰蛋白酶, Pck) 也呈现出肝脏的节律性振荡。两种处理光周期相同，在天黑前1小时喂食的处理，大脑中仍有几个时钟基因有节律性，但肝脏中的时钟基因和代谢基因都没有表现出明显的节律性振荡。本研究表明，海洋青鳉存在生物节律，且生物节律与脂质代谢密切相关。根据组2因素，发现光周期主要影响中央时钟系统，摄食时间主要影响周边时钟和代谢基因的节律性表达。该结论将为海洋青鳉提供科学高效的繁育策略。天黑前1小时喂食的处理，大脑中仍有几个时钟基因有节律性，但肝脏中的时钟基因和代谢基因都没有表现出明显的节律性振荡。本研究表明，海洋青鳉存在生物节律，且生物节律与脂质代谢密切相关。根据组2因素，发现光周期主要影响中央时钟系统，摄食时间主要影响周边时钟和代谢基因的节律性表达。该结论将为海洋青鳉提供科学高效的繁育策略。天黑前1小时喂食的处理，大脑中仍有几个时钟基因有节律性，但肝脏中的时钟基因和代谢基因都没有表现出明显的节律性振荡。本研究表明，海洋青鳉存在生物节律，且生物节律与脂质代谢密切相关。根据组2因素，发现光周期主要影响中央时钟系统，摄食时间主要影响周边时钟和代谢基因的节律性表达。该结论将为海洋青鳉提供科学高效的繁育策略。但肝脏中的时钟基因和代谢基因均未表现出明显的节律性振荡。本研究表明，海洋青鳉存在生物节律，且生物节律与脂质代谢密切相关。根据组2因素，发现光周期主要影响中央时钟系统，摄食时间主要影响周边时钟和代谢基因的节律性表达。该结论将为海洋青鳉提供科学高效的繁育策略。但肝脏中的时钟基因和代谢基因均未表现出明显的节律性振荡。本研究表明，海洋青鳉存在生物节律，且生物节律与脂质代谢密切相关。根据组2因素，发现光周期主要影响中央时钟系统，摄食时间主要影响周边时钟和代谢基因的节律性表达。该结论将为海洋青鳉提供科学高效的繁育策略。发现光周期主要影响中央时钟系统，摄食时间主要影响外周时钟和代谢基因的节律性表达。该结论将为海洋青鳉提供科学高效的繁育策略。发现光周期主要影响中央时钟系统，摄食时间主要影响外周时钟和代谢基因的节律性表达。该结论将为海洋青鳉提供科学高效的繁育策略。