Porites' coral calcifying fluid chemistry regulation under normal- and low-pH seawater conditions in Palau Archipelago: Impacts on growth properties.

Ongoing ocean acidification is known to be a major threat to tropical coral reefs. To date, only few studies have evaluated the impacts of natural long-term exposure to low-pH seawater on the chemical regulation and growth of reef-building corals. This work investigated the different responses of the massive Porites coral living at normal (pH ~ 8.

Differences in carbonate chemistry up-regulation of long-lived reef-building corals.

With climate projections questioning the future survival of stony corals and their dominance as tropical reef builders, it is critical to understand the adaptive capacity of corals to ongoing climate change. Biological mediation of the carbonate chemistry of the coral calcifying fluid is a fundamental component for assessing the response of corals to global threats. The Tara Pacific expedition (2016-2018) provided an opportunity to investigate calcification patterns in extant corals throughout the Pacific Ocean.

Disparate genetic divergence patterns in three corals across a pan-Pacific environmental gradient highlight species-specific adaptation.

Tropical coral reefs are among the most affected ecosystems by climate change and face increasing loss in the coming decades. Effective conservation strategies that maximize ecosystem resilience must be informed by the accurate characterization of extant genetic diversity and population structure together with an understanding of the adaptive potential of keystone species. Here we analyzed samples from the Tara Pacific Expedition (2016-2018) that completed an 18,000 km longitudinal transect of the Pacific Ocean sampling three widespread corals-Pocillopora meandrina, Porites lobata, and Millepora cf.

Pervasive tandem duplications and convergent evolution shape coral genomes.

Background: Over the last decade, several coral genomes have been sequenced allowing a better understanding of these symbiotic organisms threatened by climate change. Scleractinian corals are reef builders and are central to coral reef ecosystems, providing habitat to a great diversity of species.

Results: In the frame of the Tara Pacific expedition, we assemble two coral genomes, Porites lobata and Pocillopora cf.

Endogenous viral elements reveal associations between a non-retroviral RNA virus and symbiotic dinoflagellate genomes.

Endogenous viral elements (EVEs) offer insight into the evolutionary histories and hosts of contemporary viruses. This study leveraged DNA metagenomics and genomics to detect and infer the host of a non-retroviral dinoflagellate-infecting +ssRNA virus (dinoRNAV) common in coral reefs. As part of the Tara Pacific Expedition, this study surveyed 269 newly sequenced cnidarians and their resident symbiotic dinoflagellates (Symbiodiniaceae), associated metabarcodes, and publicly available metagenomes, revealing 178 dinoRNAV EVEs, predominantly among hydrocoral-dinoflagellate metagenomes.