Role of symbiotic assemblages in coral host survival: translocation from mesophotic to shallow reef

在2018财年，我们完成了珊瑚和外共生体的移植实验，并对内共生体和外共生体进行了分子分析。我们还与北海道大学的山崎博士和渡边博士合作，从原始和两个移植深度取样的水和珊瑚中进行了营养和稳定同位素测量。此外，JSPS研究员Rouze博士访问了我校Iriomote Station的甲壳类分类学专家Naruse博士，共同对一种新的外共生物种进行了分类学研究。该项目获得的初步数据于2018年6月在美国举行的戈登中孔珊瑚生态系统会议上发表。内共生菌（Symbiodiniaceae）高通量测序获得的大量数据仍在分析中，但初步结果表明，与qPCR获得的定量结果相比，深度上的定性相对稳定。与此同时，稳定同位素分析证明了丝叶珊瑚的营养可塑性。报道这些发现的手稿目前正在定稿，而一份关于鹿角珊瑚和四足蟹之间共生关系早期发生的手稿已于2019年4月发表。

In FY2018, we finished the transplantation experiment with the final samplings of the corals and exosymbionts and the molecular analyses of both endo- and exosymbionts. We also performed nutriment and stable isotopes measurements from water sampled at the original and two transplant depths and the corals in collaboration with Dr. Yamazaki and Dr. Watanabe at Hokkaido University. In addition, Dr. Rouze, the JSPS fellow, visited Dr. Naruse, an expert in crustacean taxonomy in Iriomote Station of our University to work together on the taxonomy of a new exosymbiont species. The preliminary data obtained in this project were presented at the Gordon Conference on Mesophotic Coral Ecosystems in USA in June 2018.The massive amount of data obtained by high throughput sequencing of the endosymbionts (Symbiodiniaceae) is still being analysed but the first results suggest a relative qualitative stability over depth contrasting with the quantitative results obtained by qPCR. In parallel, the stable isotopes analyses evidenced the nutritional plasticity of the coral Seriatopora hystrix.Manuscripts reporting these finding are currently being finalized, while a manuscript on the early onset of the symbiosis between Acropora corals and Tetralia crabs has been published in April 2019.