Rinsky Mieka, Weizman Eviatar, Ben-Asher Hiba Waldman, Eyal Gal, Zhu Bokai, Levy Oren
Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel.
ARC Centre of Excellence for Coral Reef Studies, School of Biological Sciences, University of Queensland St. Lucia, Queensland 4072, Australia.
Sci Adv. 2022 Sep 16;8(37):eabo6467. doi: 10.1126/sciadv.abo6467.
Studying chronobiology in reef-building corals is challenging due to the tightly coupled symbiosis with their photosynthetic algae, Symbiodiniaceae. Although symbiosis requires metabolic synchronization and coordination of cellular processes in the holobiont, the cross-talk between the host and symbiont's clocks is still puzzling. Here, we use the mesophotic coral to examine temporal gene expression patterns in symbiotic and aposymbiotic morphs exposed to natural light/dark cycles and constant darkness. Our comparative transcriptomic analyses revealed circadian and circatidal cycles of gene expression with a predominant diel pattern in both coral morphs. We found a substantial number of transcripts consistently rhythmic under both light conditions, including genes likely involved in the cnidarians' circadian clock, thus indicating that an endogenous clock, which can oscillate independently from the Symbiodiniaceae clock, exists in . The analysis further manifests the remarkable impacts of symbiosis on transcriptional rhythms and implies that the algae's presence influences the host's biorhythm.
由于与光合藻类共生藻（Symbiodiniaceae）紧密耦合的共生关系，研究造礁珊瑚的生物钟学具有挑战性。尽管共生需要全生物中细胞过程的代谢同步和协调，但宿主和共生体生物钟之间的相互作用仍然令人困惑。在这里，我们使用中光层珊瑚来研究共生和非共生形态在自然光照/黑暗周期和持续黑暗条件下的时间基因表达模式。我们的比较转录组分析揭示了两种珊瑚形态中基因表达的昼夜节律和潮汐节律，且以主要的昼夜模式为主。我们发现大量转录本在两种光照条件下都始终呈现节律性，包括可能参与刺胞动物生物钟的基因，这表明中光层珊瑚中存在一个可以独立于共生藻生物钟振荡的内源性生物钟。该分析进一步表明共生对转录节律有显著影响，并暗示藻类的存在会影响宿主的生物节律。
