University of Zurich, Department of Molecular Life Sciences, Zurich, Switzerland.
Lab for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.
Elife. 2021 Sep 22;10:e68903. doi: 10.7554/eLife.68903.
Eukaryotes generally display a circadian rhythm as an adaption to the reoccurring day/night cycle. This is particularly true for visual physiology that is directly affected by changing light conditions. Here we investigate the influence of the circadian rhythm on the expression and function of visual transduction cascade regulators in diurnal zebrafish and nocturnal mice. We focused on regulators of shut-off kinetics such as Recoverins Arrestins Opsin kinases and Regulator of G-protein signaling that have direct effects on temporal vision. Transcript as well as protein levels of most analyzed genes show a robust circadian rhythm-dependent regulation, which correlates with changes in photoresponse kinetics. Electroretinography demonstrates that photoresponse recovery in zebrafish is delayed in the evening and accelerated in the morning. Functional rhythmicity persists in continuous darkness, and it is reversed by an inverted light cycle and disrupted by constant light. This is in line with our finding that orthologous gene transcripts from diurnal zebrafish and nocturnal mice are often expressed in an anti-phasic daily rhythm.
真核生物通常表现出昼夜节律，以适应反复出现的昼夜循环。对于直接受光照条件变化影响的视觉生理学来说，这一点尤其正确。在这里，我们研究了昼夜节律对视觉转导级联调节因子在昼行性斑马鱼和夜行性小鼠中的表达和功能的影响。我们重点研究了关闭动力学的调节剂，如恢复蛋白、抑制蛋白、视蛋白激酶和 G 蛋白信号调节因子，它们对视知觉有直接影响。大多数分析基因的转录本和蛋白水平都表现出强烈的昼夜节律依赖性调节，与光反应动力学的变化相关。视网膜电图显示，斑马鱼的光反应恢复在晚上延迟，在早上加速。在连续黑暗中，功能节律仍然存在，它被颠倒的光周期逆转，并被持续的光照破坏。这与我们的发现一致，即来自昼行性斑马鱼和夜行性小鼠的同源基因转录本通常以相反的相位表达每日节律。
