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ZooKeys 2024A new zooxanthellate scleractinian coral, Kishi, Nomura & Fukami, (Scleractinia, Merulinidae), is described from non-coral reef regions of Japan and northern Taiwan....
A new zooxanthellate scleractinian coral, Kishi, Nomura & Fukami, (Scleractinia, Merulinidae), is described from non-coral reef regions of Japan and northern Taiwan. This new species was previously recognized as a morphological variant of (Veron, 1990) and can be morphologically distinguished from that species by lacking groove-and-tube structures on corallite wall joints, and by having larger calices, numerous septa, and up to three corallites in one valley. The new species also formed an independent clade from its congeners, (Milne Edwards & Haime, 1857), and (Wells, 1954), in the molecular phylogeny based on the mitochondrial intergenic region and nuclear ribosomal internal transcribed spacers.
PubMed: 38957220
DOI: 10.3897/zookeys.1205.121507 -
BioRxiv : the Preprint Server For... Nov 2023Cnidarians have become valuable models for understanding many aspects of developmental biology including the evolution of body plan diversity, novel cell type...
UNLABELLED
Cnidarians have become valuable models for understanding many aspects of developmental biology including the evolution of body plan diversity, novel cell type specification, and regeneration. Most of our understanding of gene function during early development in cnidarians comes from a small number of experimental systems including the sea anemone, . Few molecular tools have been developed for use in hard corals, limiting our understanding of this diverse and ecologically important clade. Here, we report the development of a suite of tools for manipulating and analyzing gene expression during early development in the northern star coral, . We present methods for gene knockdown using short hairpin RNAs, gene overexpression using exogenous mRNAs, and endogenous gene tagging using CRISPR-mediated gene knock-in. Combined with our ability to control spawning in the laboratory, these tools make a tractable experimental system for investigative studies of coral development. Further application of these tools will enable functional analyses of embryonic patterning and morphogenesis across Anthozoa and open new frontiers in coral biology research.
SUMMARY STATEMENT
This study reports the development of the first transgenic knock-in coral, providing the opportunity to track the behavior of various cell types during early coral development.
PubMed: 38948709
DOI: 10.1101/2023.11.16.567385 -
Methods in Enzymology 2024Coral terpenes are important molecules with numerous applications. Here, we describe a robust and simple method to produce coral terpene scaffolds at scale. As an...
Coral terpenes are important molecules with numerous applications. Here, we describe a robust and simple method to produce coral terpene scaffolds at scale. As an example of the approach, here we discover, express, and characterize further klysimplexin R synthases, expanding the known enzymology of soft coral terpene cyclases. We hope that the underlying method described will enable widespread basic research into the functions of coral terpenes and their biosynthetic genes, as well as the commercial development of biomedically and technologically important molecules.
Topics: Anthozoa; Terpenes; Animals; Saccharomyces cerevisiae; Escherichia coli; Alkyl and Aryl Transferases
PubMed: 38942511
DOI: 10.1016/bs.mie.2024.03.023 -
Methods in Enzymology 2024Octocorals are the most prolific source of terpenoids in the marine environment, with more than 4000 different compounds known from the phylum to date. However, the...
Octocorals are the most prolific source of terpenoids in the marine environment, with more than 4000 different compounds known from the phylum to date. However, the biochemical and genetic origin of their production remained elusive until recent studies showed that octocorals encode genes responsible for the biosynthesis of terpenoids in their own chromosomal DNA rather than from microbial symbionts as originally proposed. The identified coral genes include those encoding a new group of class I terpene cyclases (TCs) clustered among other candidate classes of tailoring enzymes. Phylogenetic analyses established octocoral TCs as a monophyletic clade, distinct from TCs of plants, bacteria, and other organisms. The newly discovered group of TCs appears to be ubiquitous in octocorals and is evolutionarily ancient. Given the recent discovery of octocoral terpenoid biochemistry and only limited genomic data presently available, there is substantial potential for discovering new biosynthetic pathways from octocorals for terpene production. The following chapter outlines practical experimental procedures for octocoral DNA and RNA extraction, genome and transcriptome assembly and mining, TC cloning and gene expression, protein purification, and in vitro analyses.
Topics: Anthozoa; Terpenes; Animals; Phylogeny; Cloning, Molecular; Alkyl and Aryl Transferases
PubMed: 38942510
DOI: 10.1016/bs.mie.2024.02.011 -
Science Advances Jun 2024Spatial and temporal patterns of future coral bleaching are uncertain, hampering global conservation efforts to protect coral reefs against climate change. Our analysis...
Spatial and temporal patterns of future coral bleaching are uncertain, hampering global conservation efforts to protect coral reefs against climate change. Our analysis of daily projections of ocean warming establishes the severity, annual duration, and onset of severe bleaching risk for global coral reefs this century, pinpointing vital climatic refugia. We show that low-latitude coral regions are most vulnerable to thermal stress and will experience little reprieve from climate mitigation. By 2080, coral bleaching is likely to start on most reefs in spring, rather than late summer, with year-round bleaching risk anticipated to be high for some low-latitude reefs regardless of global efforts to mitigate harmful greenhouse gasses. By identifying Earth's reef regions that are at lowest risk of accelerated bleaching, our results will prioritize efforts to limit future loss of coral reef biodiversity.
Topics: Coral Reefs; Climate Change; Animals; Anthozoa; Coral Bleaching; Conservation of Natural Resources; Biodiversity; Global Warming
PubMed: 38924396
DOI: 10.1126/sciadv.adn9660 -
PloS One 2024The effects of turbidity and sedimentation stress on early life stages of corals are poorly understood, particularly in Atlantic species. Dredging operations, beach...
The effects of turbidity and sedimentation stress on early life stages of corals are poorly understood, particularly in Atlantic species. Dredging operations, beach nourishment, and other coastal construction activities can increase sedimentation and turbidity in nearby coral reef habitats and have the potential to negatively affect coral larval development and metamorphosis, reducing sexual reproduction success. In this study, we investigated the performance of larvae of the threatened Caribbean coral species Orbicella faveolata exposed to suspended sediments collected from a reef site in southeast Florida recently impacted by dredging (Port of Miami), and compared it to the performance of larvae exposed to sediments collected from the offshore, natal reef of the parent colonies. In a laboratory experiment, we tested whether low and high doses of each of these sediment types affected the survival, settlement, and respiration of coral larvae compared to a no-sediment control treatment. In addition, we analyzed the sediments used in the experiments with 16S rRNA gene amplicon sequencing to assess differences in the microbial communities present in the Port versus Reef sediments, and their potential impact on coral performance. Overall, only O. faveolata larvae exposed to the high-dose Port sediment treatment had significantly lower survival rates compared to the control treatment, suggesting an initial tolerance to elevated suspended sediments. However, significantly lower settlement rates were observed in both Port treatments (low- and high-dose) compared to the control treatment one week after exposure, suggesting strong latent effects. Sediments collected near the Port also contained different microbial communities than Reef sediments, and higher relative abundances of the bacteria Desulfobacterales, which has been associated with coral disease. We hypothesize that differences in microbial communities between the two sediments may be a contributing factor in explaining the observed differences in larval performance. Together, these results suggest that the settlement success and survival of O. faveolata larvae are more readily compromised by encountering port inlet sediments compared to reef sediments, with potentially important consequences for the recruitment success of this species in affected areas.
Topics: Animals; Anthozoa; Larva; Geologic Sediments; Coral Reefs; Endangered Species; RNA, Ribosomal, 16S; Florida; Microbiota
PubMed: 38923956
DOI: 10.1371/journal.pone.0292474 -
Global Change Biology Jun 2024Climate change poses an existential threat to coral reefs. A warmer and more acidic ocean weakens coral ecosystems and increases the intensity of hurricanes. The...
Climate change poses an existential threat to coral reefs. A warmer and more acidic ocean weakens coral ecosystems and increases the intensity of hurricanes. The wind-wave-current interactions during a hurricane deeply change the ocean circulation patterns and hence potentially affect the dispersal of coral larvae and coral disease agents. Here, we modeled the impact of major hurricane Irma (September 2017) on coral larval and stony coral tissue loss disease (SCTLD) connectivity in Florida's Coral Reef. We coupled high-resolution coastal ocean circulation and wave models to simulate the dispersal of virtual coral larvae and disease agents between thousands of reefs. While being a brief event, our results suggest the passage of hurricane Irma strongly increased the probability of long-distance exchanges while reducing larval supply. It created new connections that could promote coral resilience but also probably accelerated the spread of SCTLD by about a month. As they become more intense, hurricanes' double-edged effect will become increasingly pronounced, contributing to increased variability in transport patterns and an accelerated rate of change within coral reef ecosystems.
Topics: Cyclonic Storms; Anthozoa; Animals; Coral Reefs; Climate Change; Florida; Larva; Models, Theoretical
PubMed: 38923652
DOI: 10.1111/gcb.17382 -
Marine Drugs Jun 2024A marine-derived fungal strain, sp. ITBBc1, was isolated from coral collected from the South China Sea in Hainan province. Intensive chemical investigation of the...
A marine-derived fungal strain, sp. ITBBc1, was isolated from coral collected from the South China Sea in Hainan province. Intensive chemical investigation of the fermentation extract of this strain afforded four new secondary metabolites (-), named megastigmanones A-C and prenylterphenyllin H, along with four known compounds (-). Their structures were elucidated by extensive spectroscopic analysis including one-and two-dimensional (1D and 2D) NMR spectroscopy and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS). The modified Mosher's method was undertaken to determine the absolute configurations of new compounds. The phytotoxic activity test showed that compounds - exhibited significant antagonistic activity against the germination of L. and L. seeds with a dose-dependent relationship.
Topics: Aspergillus; Anthozoa; Animals; Triticum; Oryza; Secondary Metabolism; Magnetic Resonance Spectroscopy; Seeds; China; Germination; Molecular Structure
PubMed: 38921581
DOI: 10.3390/md22060270 -
PloS One 2024Geochemical proxies of sea surface temperature (SST) and seawater pH (pHsw) in scleractinian coral skeletons are valuable tools for reconstructing tropical climate...
Geochemical proxies of sea surface temperature (SST) and seawater pH (pHsw) in scleractinian coral skeletons are valuable tools for reconstructing tropical climate variability. However, most coral skeletal SST and pHsw proxies are univariate methods that are limited in their capacity to circumvent non-climate-related variability. Here we present a novel multivariate method for reconstructing SST and pHsw from the geochemistry of coral skeletons. Our Scleractinian Multivariate Isotope and Trace Element (SMITE) method optimizes reconstruction skill by leveraging the covariance across an array of coral elemental and isotopic data with SST and pHsw. First, using a synthetic proxy experiment, we find that SMITE SST reconstruction statistics (correlation, accuracy, and precision) are insensitive to noise and variable calibration period lengths relative to Sr/Ca. While SMITE pHsw reconstruction statistics remain relative to δ11B throughout the same synthetic experiment, the magnitude of the long-term trend in pHsw is progressively lost under conditions of moderate-to-high analytical uncertainty. Next, we apply the SMITE method to an array of seven coral-based geochemical variables (B/Ca, δ11B, Li/Ca, Mg/Ca, Sr/Ca, U/Ca & Li/Mg) measured from two Bermudan Porites astreoides corals. Despite a <3.5 year calibration period, SMITE SST and pHsw estimates exhibit significantly better accuracy, precision, and correlation with their respective climate targets than the best single- and dual-proxy estimators. Furthermore, SMITE model parameters are highly reproducible between the two coral cores, indicating great potential for fossil applications (when preservation is high). The results shown here indicate that the SMITE method can outperform the most common coral-based SST and pHsw reconstructions methods to date, particularly in datasets with a large variety of geochemical variables. We therefore provide a list of recommendations and procedures for users to begin implementing the SMITE method as well as an open-source software package to facilitate dissemination of the SMITE method.
Topics: Seawater; Hydrogen-Ion Concentration; Anthozoa; Animals; Temperature; Trace Elements
PubMed: 38917168
DOI: 10.1371/journal.pone.0305607 -
Scientific Reports Jun 2024The application of beneficial microorganisms for corals (BMC) decreases the bleaching susceptibility and mortality rate of corals. BMC selection is typically performed...
The application of beneficial microorganisms for corals (BMC) decreases the bleaching susceptibility and mortality rate of corals. BMC selection is typically performed via molecular and biochemical assays, followed by genomic screening for BMC traits. Herein, we present a comprehensive in silico framework to explore a set of six putative BMC strains. We extracted high-quality DNA from coral samples collected from the Red Sea and performed PacBio sequencing. We identified BMC traits and mechanisms associated with each strain as well as proposed new traits and mechanisms, such as chemotaxis and the presence of phages and bioactive secondary metabolites. The presence of prophages in two of the six studied BMC strains suggests their possible distribution within beneficial bacteria. We also detected various secondary metabolites, such as terpenes, ectoines, lanthipeptides, and lasso peptides. These metabolites possess antimicrobial, antifungal, antiviral, anti-inflammatory, and antioxidant activities and play key roles in coral health by reducing the effects of heat stress, high salinity, reactive oxygen species, and radiation. Corals are currently facing unprecedented challenges, and our revised framework can help select more efficient BMC for use in studies on coral microbiome rehabilitation, coral resilience, and coral restoration.
Topics: Anthozoa; Animals; Indian Ocean; Probiotics; Genomics; Bacteria; Microbiota
PubMed: 38914624
DOI: 10.1038/s41598-024-65152-8