Project description:Branching coral species like the Caribbean Acroporids are long lived and reproduce asexually via breakage of branches. Fragmentation is the dominant mode of local population maintenance for these corals across much of their range. Thus, large genets with many member ramets (colonies) are common. Each of the ramets experiences different microenvironments, especially with respect to light and water flow. Here, we investigate whether colonies that are members of the same genet have different epigenomes because of differences in their microenvironments. The Florida Keys experienced a large- scale coral bleaching event in 2014-2015 caused by high water temperatures. During the event, ramets of the same coral genet bleached differently. Previous work had shown that this was unlikely to be due to their eukaryotic algal symbionts (Symbiodinium ‘fitti’) because each genet of this coral species typically harbors a single strain of S. ‘fitti’. Characterization of the microbiome via 16S tag sequencing did not provide evidence for a central role of microbiome variation in determining bleaching response. Instead, epigenetic changes were significantly correlated with the host’s genetic background, the position of the sampled polyps within the colonies (e.g. tip versus base of colony), and differences in the colonies’ condition during the bleaching event. We conclude that microenvironmental differences in growing conditions led to long-term changes in the way the ramets methylated their genomes and thus to a differential bleaching response.
Project description:Branching coral species like the Caribbean Acroporids are long lived and reproduce asexually via breakage of branches. Fragmentation is the dominant mode of local population maintenance for these corals across much of their range. Thus, large genets with many member ramets (colonies) are common. Each of the ramets experiences different microenvironments, especially with respect to light and water flow. Here, we investigate whether colonies that are members of the same genet have different epigenomes because of differences in their microenvironments. The Florida Keys experienced a large- scale coral bleaching event in 2014-2015 caused by high water temperatures. During the event, ramets of the same coral genet bleached differently. Previous work had shown that this was unlikely to be due to their eukaryotic algal symbionts (Symbiodinium ‘fitti’) because each genet of this coral species typically harbors a single strain of S. ‘fitti’. Characterization of the microbiome via 16S tag sequencing did not provide evidence for a central role of microbiome variation in determining bleaching response. Instead, epigenetic changes were significantly correlated with the host’s genetic background, the position of the sampled polyps within the colonies (e.g. tip versus base of colony), and differences in the colonies’ condition during the bleaching event. We conclude that microenvironmental differences in growing conditions led to long-term changes in the way the ramets methylated their genomes and thus to a differential bleaching response.
Project description:Florida’s coral reefs are currently experiencing a multi-year disease-related mortality event, that has resulted in massive die-offs in multiple coral species. Approximately 21 species of coral, including both Endangered Species Act-listed and the primary reef-building species, have displayed tissue loss lesions which often result in whole colony mortality [Stony Coral Tissue Loss Disease (SCTLD)]. Determining the causative agent(s) of coral disease relies on a multidisciplinary approach since the causation may be a combination of abiotic, microbial or viral agents. Metaproteomics was used to survey changes in the molecular landscape in the coral holobiont with the goal of providing useful information not only in diagnosis, but for prediction and prognosis. Specifically, in the case of SCTLD, defining molecular changes in the coral holobiont will help define disease progression and aid in identifying the causative agent by clearly defining traits of disease progression shared across affected species. Using samples from nine coral species (46 samples total; those appearing healthy, n = 23, and diseased, n = 23), analysis of the coral and its associated microbiome were performed using bottom-up proteomics. Ongoing analysis (including improving coral holobiont genome-based search space) will demonstrate the utility of this approach and help define improved future experiments.
Project description:Marine sponges are essential for coral reefs to thrive and harbour a diverse microbiome that is thought to contribute to host health. Although the overall function of sponge symbionts has been increasingly described, in-depth characterisation of each taxa remains challenging, with many sponge species hosting up to 3,000 distinct microbial species. Recently, the sponge Ianthella basta has emerged as a model organism for symbiosis research, hosting only three dominant symbionts: a Thaumarchaeotum, a Gammaproteobacterium, and an Alphaproteobacterium and a range of other minor taxa. Here, we retrieved metagenome assembled genomes (MAGs) for >90% of I. basta’s microbial community which allowed us to make a complete metabolic reconstruction of the sponge’s microbiome, identifying metabolic complementarity between microbes, as well as the importance of symbionts present in low abundance. We also mined the metagenomes for putative viral sequences, highlighting the contribution of viruses to the overall metabolism of the sponge, and complement this data with metaproteomic sequencing to identify active metabolic pathways in both prokaryotes and viruses. This data now allows us to use I. basta as a model organism for studying host-microbe interactions and provides a basis for future (genomic) manipulative experiments.
2023-02-24 | PXD032278 | Pride
Project description:Vertical connectivity assessment of two coral species in Bermuda
Project description:Ammonia oxidizer community structure were examined in a depth profile from 20 to 2000 m at the Bermuda Atlantic Time-series Study using a functional gene microarray to look at amoA diversity
Project description:This studies investigates the acute response of the coral Acropora millepora to two immunogenes: MDP (bacterial mimic) and pIC (viral mimic). Three members of the GiMAP familly were found to respond strongly to MDP treatment, showing analalogy to the immune response in vertebrates and plants. Differential gene expression following treatment with two immunogenes