Algae’s evolutionary background key to future climate change protection

Crustose coralline algae, Tsoi Island Papua New Guinea. Credit: Justin Hofman

Reef-building algae have a unique molecular makeup that could help future coral reefs to withstand climate change, a world-first study published in Scientific Reports has found.

Griffith University researchers from the School of Environment and Science and the Australian Rivers Institute analysed the active gene content for four different species of crustose coralline algae (CCA), which are integral to the formation and resilience of coral reefs.

“We found heat shock protein 90 to have undergone a significant duplication event across species of CCA when compared to other red algae species. This could be linked to their evolutionary history and may help them to persist during future times of increased temperature and carbon dioxide,’’ says PhD candidate Tessa Page who co-authored the paper with Dr Carmel McDougall and Associate Professor Guillermo Diaz-Pulido.

“CCA help to build coral reefs and have a unique calcification process, which sets them apart from corals and other species of red algae. This study begins to shed light on the potential genes that may play a role in the formation of the CCA limestone skeletons (that is calcification), which is a fundamental aspect of their importance to coral reefs worldwide.

“The sequencing of genomes and/or transcriptomes provides essential information for the understanding of physiological and biological traits and responses, but until now there has been limited molecular information on these species with no transcriptomes.”

“This work is important because coral reefs depend on CCA for their ability to reef build in their own right, support and cement the structural complexity of coral reefs, and induce the settlement of economically and ecologically important invertebrates such as coral and abalone”, says Associate Professor Diaz-Pulido.