Although covering only ~0.2% of the ocean’s surface, coral reefs harbour ~25% of ocean biodiversity and provide food to nearly a billion people. Ecological services from coral reefs are essential through fisheries, tourism, coastal protection and are estimated at about 30 billions USD per year. But corals are being stressed and recent estimates indicate that ~20% of reefs have permanently disappeared and about 50% will be threatened by 2050. Coral reefs are often at the forefront of research on climate change, due to bleaching, ocean acidification, and concerns about reef growth processes.
Recent genomic developments have demonstrated the complexity of the coral genome that appears as complex as that for vertebrates. Reef corals further add to this complexity through an obligatory photo-endosymbiosis developed with microalgae. The physiological consequences of the presence of these photosynthetic microalgae (called zooxanthellae), which further add to the complexity of the coral hologenome, and the deep physio-genomic impacts resulting from this symbiosis on both partners, have yet to be fully elucidated. Furthermore, corals are hosts of a still largely unknown world of associated bacteria, viruses and other protists, forming a complex symbiocosm that biologists refer to as ‘holobiont’.
This project entitled, “Genomic complexity of the coral holobiont across biodiversity gradients in the Pacific” is ambitious and seeks to investigate the complex diversity of the coral holobiont within the context of global change. It will serve as the foundation for the new Tara Pacific expedition (2016-2018). It builds upon the experience of previous Tara-Oceans expeditions and will focus on coral reefs throughout the Pacific Ocean, drawing an east-west transect from Panama to Japan and a south-north transect from New Zealand to Japan, and will sample corals throughout roughly 35 island systems with local replicates. CORALGENE will develop and apply state-of-the-art technologies in very-high-throughput genetic sequencing to reveal the entire microbial diversity (i.e. full biological complexity) present within coral holobionts. CORALGENE brings together a consortium of international experts in marine biology and ecology, cellular and molecular biology, genomics, and bioinformatics. Though this diverse team of global coral reef experts, we will have the expertise needed to build a comprehensive morpho-molecular inventory of the biodiversity of the coral holobiont, from viruses to prokaryotes, unicellular eukaryotes, and metazoans, which will include the biodiversity from both interstitial and surrounding seawaters. This very ambitious project will reveal a massive amount of cryptic and novel biodiversity, will shed light on the complex links between genomes, transcriptomes, metabolomes, organisms, and ecosystem functions in coral reefs, and will provide a reference of the biological state of modern coral reefs for the large research community working on coral adaptation to global and regional stressors.
Monsieur Serge Planes (Centre National de la Recherche Scientifique)
The author of this summary is the project coordinator, who is responsible for the content of this summary. The ANR declines any responsibility as for its contents.
IRCAN Institute for Research on Cancer Ageing of Nice
CSM Centre Scientifique de Monaco
NUI National University Ireland, Galway
CNRS - USR3278 Centre National de la Recherche Scientifique
UMR 8030/GENOSCOPE/CEA UMR8030/GENOSCOPE/CEA
AD2M AD2M Adaptation et diversité en milieu marin
OSU Oregon State University Marine biology
TARA FONDATION TARA EXPEDITION
MARUM MARUM - Center for Marine Environment Sciences
KAUST King Abdullah University of Science and Technology
CNRS DR Bretagne Pays de la Loire CNRS DR Bretagne Pays de la Loire
Help of the ANR 649,042 euros
Beginning and duration of the scientific project: November 2017 - 48 Months