-
Marine Drugs Oct 2023Reef-building corals, recognized as cornerstone species in marine ecosystems, captivate with their unique duality as both symbiotic partners and autotrophic entities.... (Review)
Review
Reef-building corals, recognized as cornerstone species in marine ecosystems, captivate with their unique duality as both symbiotic partners and autotrophic entities. Beyond their ecological prominence, these corals produce a diverse array of secondary metabolites, many of which are poised to revolutionize the domains of pharmacology and medicine. This exhaustive review delves deeply into the multifaceted world of coral-derived lipids, highlighting both ubiquitous and rare forms. Within this spectrum, we navigate through a myriad of fatty acids and their acyl derivatives, encompassing waxes, sterol esters, triacylglycerols, mono-akyl-diacylglycerols, and an array of polar lipids such as betaine lipids, glycolipids, sphingolipids, phospholipids, and phosphonolipids. We offer a comprehensive exploration of the intricate biochemical variety of these lipids, related fatty acids, prostaglandins, and both cyclic and acyclic oxilipins. Additionally, the review provides insights into the chemotaxonomy of these compounds, illuminating the fatty acid synthesis routes inherent in corals. Of particular interest is the symbiotic bond many coral species nurture with dinoflagellates from the Symbiodinium group; their lipid and fatty acid profiles are also detailed in this discourse. This exploration accentuates the vast potential and intricacy of coral lipids and underscores their profound relevance in scientific endeavors.
Topics: Animals; Anthozoa; Ecosystem; Fatty Acids; Prostaglandins; Coral Reefs; Dinoflagellida; Symbiosis
PubMed: 37888474
DOI: 10.3390/md21100539 -
Current Biology : CB Oct 2020LaJeunesse introduces the group of unicellular microalgae referred to as 'zooxanthellae'.
LaJeunesse introduces the group of unicellular microalgae referred to as 'zooxanthellae'.
Topics: Animals; Anthozoa; Dinoflagellida; Symbiosis
PubMed: 33022248
DOI: 10.1016/j.cub.2020.03.058 -
Marine Drugs Feb 2023The heterotrophic is a major model for dinoflagellate cell biology, and a major industrial producer of docosahexaenoic acid, a key nutraceutical and added...
The heterotrophic is a major model for dinoflagellate cell biology, and a major industrial producer of docosahexaenoic acid, a key nutraceutical and added pharmaceutical compound. Despite these factors, the family Crypthecodiniaceae is not fully described, which is partly attributable to their degenerative thecal plates, as well as the lack of ribotype-referred morphological description in many taxons. We report here significant genetic distances and phylogenetic cladding that support inter-specific variations within the Crypthecodiniaceae. We describe sp. nov. Kwok, Law and Wong, that have different genome sizes, ribotypes, and amplification fragment length polymorphism profiles when compared to the . The interspecific ribotypes were supported by distinctive truncation-insertion at the ITS regions that were conserved at intraspecific level. The long genetic distances between Crypthecodiniaceae and other dinoflagellate orders support the separation of the group, which includes related taxons with high oil content and degenerative thecal plates, to be ratified to the order level. The current study provides the basis for future specific demarcation-differentiation, which is an important facet in food safety, biosecurity, sustainable agriculture feeds, and biotechnology licensing of new oleaginous models.
Topics: Dinoflagellida; Phylogeny; Docosahexaenoic Acids; Biotechnology; Heterotrophic Processes
PubMed: 36976211
DOI: 10.3390/md21030162 -
Current Biology : CB Jan 2021Tracy Ainsworth and Barbara Brown introduce the causes and consequences of coral bleaching.
Tracy Ainsworth and Barbara Brown introduce the causes and consequences of coral bleaching.
Topics: Animals; Anthozoa; Chlorophyll; Color; Conservation of Natural Resources; Coral Reefs; Dinoflagellida; Global Warming; Hot Temperature; Photobleaching; Symbiosis
PubMed: 33434489
DOI: 10.1016/j.cub.2020.10.048 -
Toxins Jul 2022is a dinoflagellate genus widely distributed throughout tropical and subtropical regions. Some members of this genus can produce a group of potent polycyclic polyether... (Review)
Review
is a dinoflagellate genus widely distributed throughout tropical and subtropical regions. Some members of this genus can produce a group of potent polycyclic polyether neurotoxins responsible for ciguatera fish poisoning (CFP), one of the most significant food-borne illnesses associated with fish consumption. Ciguatoxins and maitotoxins, the two major toxins produced by , act on voltage-gated channels and TRPA1 receptors, consequently leading to poisoning and even death in both humans and animals. Over the past few decades, the occurrence and geographic distribution of CFP have undergone a significant expansion due to intensive anthropogenic activities and global climate change, which results in more human illness, a greater public health impact, and larger economic losses. The global spread of CFP has led to and its toxins being considered an environmental and human health concern worldwide. In this review, we seek to provide an overview of recent advances in the field of and its associated toxins based on the existing literature combined with re-analyses of current data. The taxonomy, phylogenetics, geographic distribution, environmental regulation, toxin detection method, toxin biosynthesis, and pharmacology and toxicology of are summarized and discussed. We also highlight future perspectives on and its associated toxins.
Topics: Animals; Ciguatera Poisoning; Ciguatoxins; Dinoflagellida; Fishes; Foodborne Diseases; Humans
PubMed: 35878223
DOI: 10.3390/toxins14070485 -
Philosophical Transactions of the Royal... Sep 2020This review explores how microbial symbioses may have influenced and continue to influence the evolution of reef-building corals (Cnidaria; Scleractinia). The coral... (Review)
Review
This review explores how microbial symbioses may have influenced and continue to influence the evolution of reef-building corals (Cnidaria; Scleractinia). The coral holobiont comprises a diverse microbiome including dinoflagellate algae (Dinophyceae; Symbiodiniaceae), bacteria, archaea, fungi and viruses, but here we focus on the Symbiodiniaceae as knowledge of the impact of other microbial symbionts on coral evolution is scant. Symbiosis with Symbiodiniaceae has extended the coral's metabolic capacity through metabolic handoffs and horizontal gene transfer (HGT) and has contributed to the ecological success of these iconic organisms. It necessitated the prior existence or the evolution of a series of adaptations of the host to attract and select the right symbionts, to provide them with a suitable environment and to remove disfunctional symbionts. Signatures of microbial symbiosis in the coral genome include HGT from Symbiodiniaceae and bacteria, gene family expansions, and a broad repertoire of oxidative stress response and innate immunity genes. Symbiosis with Symbiodiniaceae has permitted corals to occupy oligotrophic waters as the algae provide most corals with the majority of their nutrition. However, the coral-Symbiodiniaceae symbiosis is sensitive to climate warming, which disrupts this intimate relationship, causing coral bleaching, mortality and a worldwide decline of coral reefs. This article is part of the theme issue 'The role of the microbiome in host evolution'.
Topics: Animals; Anthozoa; Biological Evolution; Dinoflagellida; Global Warming; Microbiota; Symbiosis
PubMed: 32772672
DOI: 10.1098/rstb.2019.0591 -
Nature Communications Nov 2023Microbial eukaryotes are important components of marine ecosystems, and the Marine Alveolates (MALVs) are consistently both abundant and diverse in global environmental...
Microbial eukaryotes are important components of marine ecosystems, and the Marine Alveolates (MALVs) are consistently both abundant and diverse in global environmental sequencing surveys. MALVs are dinoflagellates that are thought to be parasites of other protists and animals, but the lack of data beyond ribosomal RNA gene sequences from all but a few described species means much of their biology and evolution remain unknown. Using single-cell transcriptomes from several MALVs and their free-living relatives, we show that MALVs evolved independently from two distinct, free-living ancestors and that their parasitism evolved in parallel. Phylogenomics shows one subgroup (MALV-II and -IV, or Syndiniales) is related to a novel lineage of free-living, eukaryovorous predators, the eleftherids, while the other (MALV-I, or Ichthyodinida) is related to the free-living predator Oxyrrhis and retains proteins targeted to a non-photosynthetic plastid. Reconstructing the evolution of photosynthesis, plastids, and parasitism in early-diverging dinoflagellates shows a number of parallels with the evolution of their apicomplexan sisters. In both groups, similar forms of parasitism evolved multiple times and photosynthesis was lost many times. By contrast, complete loss of the plastid organelle is infrequent and, when this does happen, leaves no residual genes.
Topics: Animals; Parasites; Ecosystem; Phylogeny; Plastids; Photosynthesis; Dinoflagellida
PubMed: 37923716
DOI: 10.1038/s41467-023-42807-0 -
Trends in Microbiology Aug 2019Coral reefs rely upon the highly optimized coral-Symbiodiniaceae symbiosis, making them sensitive to environmental change and susceptible to anthropogenic stress. Coral... (Review)
Review
Coral reefs rely upon the highly optimized coral-Symbiodiniaceae symbiosis, making them sensitive to environmental change and susceptible to anthropogenic stress. Coral bleaching is predominantly attributed to photo-oxidative stress, yet nutrient availability and metabolism underpin the stability of symbioses. Recent studies link symbiont proliferation under nutrient enrichment to bleaching; however, the interactions between nutrients and symbiotic stability are nuanced. Here, we demonstrate how bleaching is regulated by the forms and ratios of available nutrients and their impacts on autotrophic carbon metabolism, rather than algal symbiont growth. By extension, historical nutrient conditions mediate host-symbiont compatibility and bleaching tolerance over proximate and evolutionary timescales. Renewed investigations into the coral nutrient metabolism will be required to truly elucidate the cellular mechanisms leading to coral bleaching.
Topics: Animals; Anthozoa; Carbon; Dinoflagellida; Microbiota; Nutrients; Phosphorus; Symbiosis; Thermotolerance
PubMed: 30987816
DOI: 10.1016/j.tim.2019.03.004 -
Annual Review of Genetics Nov 2023Symbiotic interactions occur in all domains of life, providing organisms with resources to adapt to new habitats. A prime example is the endosymbiosis between corals and... (Review)
Review
Symbiotic interactions occur in all domains of life, providing organisms with resources to adapt to new habitats. A prime example is the endosymbiosis between corals and photosynthetic dinoflagellates. Eukaryotic dinoflagellate symbionts reside inside coral cells and transfer essential nutrients to their hosts, driving the productivity of the most biodiverse marine ecosystem. Recent advances in molecular and genomic characterization have revealed symbiosis-specific genes and mechanisms shared among symbiotic cnidarians. In this review, we focus on the cellular and molecular processes that underpin the interaction between symbiont and host. We discuss symbiont acquisition via phagocytosis, modulation of host innate immunity, symbiont integration into host cell metabolism, and nutrient exchange as a fundamental aspect of stable symbiotic associations. We emphasize the importance of using model systems to dissect the cellular complexity of endosymbiosis, which ultimately serves as the basis for understanding its ecology and capacity to adapt in the face of climate change.
Topics: Animals; Anthozoa; Symbiosis; Ecosystem; Dinoflagellida; Systems Analysis
PubMed: 37722685
DOI: 10.1146/annurev-genet-072320-125436 -
Trends in Ecology & Evolution Mar 2024The photosynthetic symbionts of corals sustain biodiverse reefs in nutrient-poor, tropical waters. Recent genomic data illuminate the evolution of coral symbionts under... (Review)
Review
The photosynthetic symbionts of corals sustain biodiverse reefs in nutrient-poor, tropical waters. Recent genomic data illuminate the evolution of coral symbionts under genome size constraints and suggest that retention of the facultative lifestyle, widespread among these algae, confers a selective advantage when compared with a strict symbiotic existence. We posit that the coral symbiosis is analogous to a 'bioreactor' that selects winner genotypes and allows them to rise to high numbers in a sheltered habitat prior to release by the coral host. Our observations lead to a novel hypothesis, the 'stepping-stone model', which predicts that local adaptation under both the symbiotic and free-living stages, in a stepwise fashion, accelerates coral alga diversity and the origin of endemic strains and species.
Topics: Animals; Anthozoa; Coral Reefs; Dinoflagellida; Ecosystem; Biodiversity; Symbiosis
PubMed: 37953106
DOI: 10.1016/j.tree.2023.10.005