Univ Brest, Ifremer, CNRS, IRD, LEMAR, F-29280, Plouzané, France.
Ifremer, EEP, F-29280, Plouzané, France.
Nat Commun. 2020 Jul 10;11(1):3454. doi: 10.1038/s41467-020-17284-4.
Biological rhythms are a fundamental property of life. The deep ocean covers 66% of our planet surface and is one of the largest biomes. The deep sea has long been considered as an arrhythmic environment because sunlight is totally absent below 1,000 m depth. In the present study, we have sequenced the temporal transcriptomes of a deep-sea species, the ecosystem-structuring vent mussel Bathymodiolus azoricus. We reveal that tidal cycles predominate in the transcriptome and physiology of mussels fixed directly at hydrothermal vents at 1,688 m depth at the Mid-Atlantic Ridge, whereas daily cycles prevail in mussels sampled after laboratory acclimation. We identify B. azoricus canonical circadian clock genes, and show that oscillations observed in deep-sea mussels could be either a direct response to environmental stimulus, or be driven endogenously by one or more biological clocks. This work generates in situ insights into temporal organisation in a deep-sea organism.
生物节律是生命的基本特征。海洋覆盖了地球表面的 66%，是最大的生态系统之一。深海长期以来被认为是无节奏的环境，因为在 1000 米以下的深度阳光完全缺失。在本研究中，我们对深海物种——生态结构喷口贻贝 Bathymodiolus azoricus 的时间转录组进行了测序。我们揭示了潮汐周期在贻贝的转录组和生理学中占主导地位，这些贻贝直接固定在中大西洋脊 1688 米深处的热液喷口，而在实验室适应后采集的贻贝中则以日周期为主。我们鉴定了 B. azoricus 的典型生物钟基因，并表明在深海贻贝中观察到的振荡可能是对环境刺激的直接反应，也可能是由一个或多个生物钟内在驱动的。这项工作为深海生物的时间组织提供了现场见解。
