Identification of factors regulating the species specificity in coral-algae symbiosis

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K14611
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Ecology/Environment
• Research Institution: National Institute for Basic Biology
• Principal Investigator: TAKAHASHI Shunichi 基礎生物学研究所, 環境光生物学研究部門, 准教授 (80620153)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 共生 / 種特異性 / サンゴ / 褐虫藻

Outline of Final Research Achievements

Many cnidarians, including reef-building corals and sea anemones, harbor endosymbiotic dinoflagellate (genus Symbiodinium), and each host species typically associates with specific Symbiodinium phylotypes. Here we propose a new model to explain the symbiont specificity for the host in cnidarian-dinoflagellate symbiosis.
We examined the relationship between infectivity and cell size of different cultured Symbiodinium strains using a model cnidarian host, sea anemone Aiptasia. Results showed that, of the fifteen Symbiodinium strains tested, the largest four strains failed to infect. Further experiments using two different coral species demonstrated that the acceptability of large-sized Symbiodinium strains differs between coral species. These results demonstrate that species specificity is determined by the cell size (symbiont) and the maximum threshold for symbiont cell size (host).

Free Research Field

生物学