Zhang Z C, Wang Y G, Li L, Yin H D, Li D Y, Wang Y, Zhao X L, Liu Y P, Zhu Q
Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu Campus, Chengdu 611130, China.
College of Animal Science and Technology, Sichuan Agricultural University, Ya'an, Sichuan, 625014, China.
Poult Sci. 2016 Jul 1;95(7):1653-1659. doi: 10.3382/ps/pew051. Epub 2016 Mar 4.
In animals, core clock genes are expressed in many peripheral tissues throughout the body that contribute to tissue specific temporal regulation including those that comprise the reproductive system. The chicken ovulatory cycle seems to provide an example of a system in which circadian and interval timing mechanisms operate during ovulation-oviposition. However, little is known about the possible role of circadian regulation during egg formation and laying. To this end, we determined the rhythmic expression of several known canonical clock genes and clock controlled genes in the 4 segments of the chicken oviduct (infundibulum, magnum, isthmus, and uterus) taken from the same biological state (laying sequence and oviposition time) using real time RT-PCR. Except for Cry1, the other genes we analyzed were expressed in all 4 segments of the oviduct. Intriguingly, in a daily light-dark cycle, Bmal1, Clock, Per2, Per3, Cry2, and Rev-erbβ have highly significant rhythmic expression in the infundibulum and uterus but not in the magnum and isthmus. These results show that there is spatial specificity in the localization of clock cells in the hen reproductive tract and that peripheral clocks might have a direct role in the infundibulum and uterus where yolk is captured and the eggshell is formed, respectively.
在动物中，核心生物钟基因在遍布全身的许多外周组织中表达，这些组织有助于组织特异性的时间调节，包括那些构成生殖系统的组织。鸡的排卵周期似乎提供了一个例子，说明昼夜节律和间隔计时机制在排卵 - 产卵过程中发挥作用。然而，关于昼夜节律调节在鸡蛋形成和产卵过程中可能发挥的作用，我们知之甚少。为此，我们使用实时逆转录 - 聚合酶链反应（RT-PCR），测定了取自相同生理状态（产蛋顺序和产卵时间）的鸡输卵管4个节段（漏斗部、膨大部、峡部和子宫）中几种已知的典型生物钟基因和生物钟调控基因的节律性表达。除了Cry1之外，我们分析的其他基因在输卵管的所有4个节段中均有表达。有趣的是，在昼夜明暗循环中，Bmal1、Clock、Per2、Per3、Cry2和Rev-erbβ在漏斗部和子宫中有高度显著的节律性表达，但在膨大部和峡部中则没有。这些结果表明，母鸡生殖道中生物钟细胞的定位存在空间特异性，并且外周生物钟可能分别在捕获卵黄的漏斗部和形成蛋壳的子宫中发挥直接作用。
