Journal article

Heat-evolved microalgal symbionts increase coral bleaching tolerance

P Buerger, C Alvarez-Roa, CW Coppin, SL Pearce, LJ Chakravarti, JG Oakeshott, R Edwards, MJH van Oppen



Coral reefs worldwide are suffering mass mortalities from marine heat waves. With the aim of enhancing coral bleaching tolerance, we evolved 10 clonal strains of a common coral microalgal endosymbiont at elevated temperatures (31°C) for 4 years in the laboratory. All 10 heat-evolved strains had expanded their thermal tolerance in vitro following laboratory evolution. After reintroduction into coral host larvae, 3 of the 10 heat-evolved endosymbionts also increased the holobionts' bleaching tolerance. Although lower levels of secreted reactive oxygen species (ROS) accompanied thermal tolerance of the heat-evolved algae, reduced ROS secretion alone did not predict thermal tolerance in symbiosi..

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University of Melbourne Researchers


Awarded by Australian Research Council Laureate Fellowship

Funding Acknowledgements

The research was funded by a CSIRO Research Office Postdoctoral Fellowship to P.B., CSIRO Land & Water, the University of Melbourne, Paul G. Allen Philanthropies, and the Australian Institute of Marine Science. Next-generation sequencing was funded by an Illumina NovaSeq mini-grant, administered through the Ramaciotti Centre, Sydney. The authors gratefully acknowledge the Ramaciotti Centre and Illumina for their support. M.J.H.v.O. acknowledges the Australian Research Council Laureate Fellowship FL180100036.