ELUCIDATING THE MECHANISMS OF STRESS TOLERANCE IN REEF-BUILDING CORAL HOLOBIONTS DOI Creative Commons
Emma Strand

Published: Jan. 1, 2023

Coral reefs worldwide are threatened by climate change effects like increasing ocean warming and acidification. These increased pressures cause a dysbiosis between the coral host, algal endosymbionts, associated microbiome that results in host expelling leaving with stark white ‘bleached’ appearance. Without their hosts forced to sustain themselves energetically heterotrophy instead of relying on autotrophic carbon energy sources once came from endosymbionts. When this response, termed ‘coral bleaching’, happens reef-wide during an extreme wave temperatures, is called mass Bleaching Event. The frequency intensity events around world, forcing corals acclimatize survive. This dissertation investigates physiological genomic mechanisms underlying acclimatization stress tolerance two common, reef-building corals: Montipora capitata Pocillopora acuta. In three chapters, I present findings support phenotypic plasticity M. hypothesize contributing this. Chapter 1, conducted ex-situ experiment mimicked environmentally realistic, extended heatwave acidification scenario factorial design temperature pCO2 conditions for two-month period recovery period. Both species’ states were significantly challenged but displayed more favorable photosynthetic rate antioxidant capacity ratio thermally tolerant symbionts. Although survived at higher rates than P. acuta, state was still impacted after months recovery, suggesting marine heatwaves likely induce legacies may impact performance next, inevitable heatwave. 2, further investigated acuta’s response 1 level. We sought test environmental stressors gene body DNA methylation patterns elucidate how sensitive dynamic changes invertebrates. However, when analyzing expression data, our team found polyploidy prevalent samples, which convoluted ability effect addition structure. followed genetic lineage diploid exhibiting highest levels despite lower epigenetic machinery proteins. Despite significant pattern differences polyploidies, acuta populations severely declined (outlined 1), regardless differential ploidy status, species be ultimately too future conditions. 3, capitata, directly comparing bleached (‘Susceptible’) non-bleached (‘Resistant’) phenotypes conspecific pairs. very little diversity among samples there no structure variation context. ‘Resistant’ characterized association symbionts, variability, genes involved death robust cellular response. all chapters suggest both stats bleaching susceptibility phenotype not one mechanism act alone produce particular phenotype. aids elucidating corals, guiding current knowledge face change.

Language: Английский

Ploidy variation and its implications for reproduction and population dynamics in two sympatric Hawaiian coral species DOI Creative Commons
Timothy G. Stephens, Emma Strand, Hollie M. Putnam

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2021, Volume and Issue: unknown

Published: Nov. 22, 2021

Abstract Standing genetic variation is a major driver of fitness and resilience, therefore fundamental importance for threatened species such as stony corals. We analyzed RNA- seq data generated from 132 Montipora capitata 119 Pocillopora acuta coral colonies collected Kāneʻohe Bay, Oʻahu, Hawaiʻi. Our goals were to determine the extent colony study reproductive strategies in these two sympatric species. Surprisingly, we found that 63% P. triploid, with putative independent origins different triploid clades. These corals have spread primarily via asexual reproduction are descended small number genotypes, whose diploid ancestor invaded bay. In contrast, all M. diploid, outbreeding, almost genetically distinct. Only cases reproduction, likely fragmentation, identified this report distinct inhabit largest sheltered body water main Hawaiian Islands. highlight divergence behavior genome biology, both which contribute resilience persistence. Significance Statement Given threat posed reef ecosystems by human caused climate change, there growing focus on developing protection restoration critical marine habitats. efforts however limited our understanding diversity survival strategies. analysis inhabiting same bay one strict sexual outbreeder, whereas other reproduces predominantly asexually (i.e., clonally) includes diploids triploids. results broaden adaptability, evolution, underpin future research into mechanisms can inform activities.

Language: Английский

Citations

10
Genomic comparison of the temperate coralAstrangia poculatawith tropical corals yields insights into winter quiescence, innate immunity, and sexual reproduction DOI Creative Commons
Kathryn H. Stankiewicz, Nadège Guiglielmoni, Sheila A. Kitchen

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Sept. 23, 2023

Abstract Facultatively symbiotic corals provide important experimental models to explore the establishment, maintenance, and breakdown of mutualism between members algal family Symbiodiniaceae. The temperate coral Astrangia poculata is one such model as it not only facultatively symbiotic, but also occurs across a broad temperature latitudinal gradient. Here, we report de novo chromosome-scale assembly annotation A. genome. Though widespread segmental/tandem duplications genomic regions were detected, did find strong evidence whole genome duplication (WGD) event. Comparison gene arrangement tropical Acropora millepora revealed 56.38% orthologous genes conserved in syntenic blocks despite ∼415 million years divergence. Gene families related sperm hyperactivation innate immunity, including lectins, found contain more relative . Sperm expected given extreme requirements gamete competition during mass spawning events corals, while lectins are establishment coral-algal symbiosis. By contrast, involved sleep promotion, feeding suppression, circadian sleep/wake cycle processes expanded These may play role ’s ability enter dormancy-like state (“winter quiescence”) survive freezing temperatures at northern edges species’ range.

Language: Английский

Citations

3
Unlocking the treasure trove: leveraging dry coral specimens for museum genomics DOI
Michael T. Connelly, Mary Grace Catapang, Andrea M. Quattrini

et al.

Coral Reefs, Journal Year: 2024, Volume and Issue: 43(4), P. 1153 - 1159

Published: June 28, 2024

Language: Английский

Citations

0
Genomes of the Caribbean reef-building corals Colpophyllia natans, Dendrogyra cylindrus, and Siderastrea siderea DOI Creative Commons
Nicolas S. Locatelli, Iliana B. Baums

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Aug. 22, 2024

Corals populations worldwide are declining rapidly due to elevated ocean temperatures and other human impacts. The Caribbean harbors a high number of threatened, endangered, critically endangered coral species compared reefs the larger Indo-Pacific. reef corals also long diverged from their Pacific counterparts may have evolved different survival strategies. Most genomic resources been developed for which impede our ability study changes in genetic composition communities response global change. To help fill gap resources, we used PacBio HiFi sequencing generate first genome assemblies three Caribbean, reef-building corals, Colpophyllia natans, Dendrogyra cylindrus, Siderastrea siderea. We explore novelties that shape scleractinian genomes. Notably, find abundant gene duplications all classes (e.g., tandem segmental), especially S. This has one largest genomes any (822Mb) seems be driven by repetitive content family expansion diversification. As size siderea was double expected stony evaluated possibility an ancient whole duplication using Ks tests found no evidence such event species. By presenting these assemblies, hope develop better understanding evolution as enable researchers further investigate population genetics diversity

Language: Английский

Citations

0
Machine Learning Approaches for Classifying and Characterizing Coral Diseases DOI
Emily W. Van Buren, Kelsey M. Beavers,

Mariah N. Cornelio

et al.

Research Square (Research Square), Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 19, 2024

Abstract Background: Anthropogenic climate change has had devastating effects on the Florida and Caribbean reef systems, primarily due to increased disease outbreaks. Climate contributes rising frequency of marine diseases by expanding pathogen ranges heightening host susceptibility environmental stress. Specifically, there been a stark rise in events targeting multiple coral species, resulting high mortality rates declining biodiversity. Although many these present similar visual symptoms, they exhibit varying require distinct treatment protocols. Advances transcriptomics research have enhanced our understanding responses different diseases, but more sophisticated methods are required classify that appear visually similar. Results: This study provides first machine learning algorithm can two common diseases: stony tissue loss (SCTLD) white plague (WP). This also identifies 463 biomarkers, with 275 unique SCTLD 167 WP. These biomarkers highlight differences immune algorithms were tested validated samples collected in situ, supporting biomarker efficacy identified for classification. The final model was built partial least squares discriminant analysis highly predictive an AUC 0.9895 low error rates. Conclusion: study provides diagnostic tool reliably distinguishes between phenotypically provide characterizations

Language: Английский

Citations

0
Ancient Hybridisation Fuelled Diversification in Acropora Corals DOI Creative Commons
Tianzhen Wu,

Alan Ningyuan Xu,

Yanli Lei

et al.

Molecular Ecology, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 13, 2024

ABSTRACT Introgression is the infiltration or flow of genes from one species to another through hybridisation followed by backcrossing. This may lead incorrect phylogenetic reconstruction divergence‐time estimation. Acropora a dominant genus reef‐building corals; however, whether this group has an introgression history before their diversification remains unclear, and previous estimates have not considered impact introgression. In study, we broke limitation few proved existence ancient in evolution whole‐genome protein‐coding sequences. We inferred 21.9% all triplet loci (homologous three different species) with series events genetic material contribution up 30.9% diversification. Furthermore, 7756 nuclear were clustered into groups using multidimensional scaling algorithm, heterogeneity which resulted relationships. The time was estimated be middle late Miocene when retained only gene lowest degree collision Australia Pacific arcs Southeast Asian margin early Miocene, cooling provide geographical climatic conditions for , respectively. Therefore, our results indicate that at genome‐wide level, introgressive promoted radiation . Based on results, influence should taken account reconstructing relationships evaluating divergence time.

Language: Английский

Citations

0
Genome assembly of the deep-sea coralLophelia pertusa DOI Creative Commons
Santiago Herrera, Erik E. Cordes

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Feb. 27, 2023

Abstract Like their shallow-water counterparts, cold-water corals create reefs that support highly diverse communities, and these structures are subject to numerous anthropogenic threats. Here, we present the genome assembly of Lophelia pertusa from southeastern coast USA, first one for a deep-sea scleractinian coral species. We generated PacBio CLR data an initial proximity ligation scaffolding. The was annotated using evidence transcripts, proteins, ab initio gene model predictions. This is comparable high-quality reference genomes corals. comprises 2,858 scaffolds (N50 1.6 Mbp) has size 556.9 Mbp. Approximately 57% repetitive elements 34% coding DNA. predicted 41,089 genes, including 91.1% complete metazoan orthologs. will facilitate investigations into ecology this species evolution

Language: Английский

Citations

1
ELUCIDATING THE MECHANISMS OF STRESS TOLERANCE IN REEF-BUILDING CORAL HOLOBIONTS DOI Creative Commons
Emma Strand

Published: Jan. 1, 2023

Coral reefs worldwide are threatened by climate change effects like increasing ocean warming and acidification. These increased pressures cause a dysbiosis between the coral host, algal endosymbionts, associated microbiome that results in host expelling leaving with stark white ‘bleached’ appearance. Without their hosts forced to sustain themselves energetically heterotrophy instead of relying on autotrophic carbon energy sources once came from endosymbionts. When this response, termed ‘coral bleaching’, happens reef-wide during an extreme wave temperatures, is called mass Bleaching Event. The frequency intensity events around world, forcing corals acclimatize survive. This dissertation investigates physiological genomic mechanisms underlying acclimatization stress tolerance two common, reef-building corals: Montipora capitata Pocillopora acuta. In three chapters, I present findings support phenotypic plasticity M. hypothesize contributing this. Chapter 1, conducted ex-situ experiment mimicked environmentally realistic, extended heatwave acidification scenario factorial design temperature pCO2 conditions for two-month period recovery period. Both species’ states were significantly challenged but displayed more favorable photosynthetic rate antioxidant capacity ratio thermally tolerant symbionts. Although survived at higher rates than P. acuta, state was still impacted after months recovery, suggesting marine heatwaves likely induce legacies may impact performance next, inevitable heatwave. 2, further investigated acuta’s response 1 level. We sought test environmental stressors gene body DNA methylation patterns elucidate how sensitive dynamic changes invertebrates. However, when analyzing expression data, our team found polyploidy prevalent samples, which convoluted ability effect addition structure. followed genetic lineage diploid exhibiting highest levels despite lower epigenetic machinery proteins. Despite significant pattern differences polyploidies, acuta populations severely declined (outlined 1), regardless differential ploidy status, species be ultimately too future conditions. 3, capitata, directly comparing bleached (‘Susceptible’) non-bleached (‘Resistant’) phenotypes conspecific pairs. very little diversity among samples there no structure variation context. ‘Resistant’ characterized association symbionts, variability, genes involved death robust cellular response. all chapters suggest both stats bleaching susceptibility phenotype not one mechanism act alone produce particular phenotype. aids elucidating corals, guiding current knowledge face change.

Language: Английский

Citations

0