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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 -
Trends in Parasitology Feb 2023
Topics: Dinoflagellida; Sequence Analysis, DNA
PubMed: 36522232
DOI: 10.1016/j.pt.2022.11.009 -
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 -
Gene Jun 2022Dinoflagellates are a vital diverse family of unicellular algae widespread in various aquatic environments. Typically large genomes and permanently condensed chromosomes... (Review)
Review
Dinoflagellates are a vital diverse family of unicellular algae widespread in various aquatic environments. Typically large genomes and permanently condensed chromosomes without histones make these organisms unique among eukaryotes in terms of chromatin structure and gene expression. Genomic and transcriptomic sequencing projects have provided new insight into the genetic foundation of dinoflagellate behaviors. Genes in tandem arrays, trans-splicing of mRNAs and lower levels of transcriptional regulation compared to other eukaryotes all contribute to the differences seen. Here we present a general overview of transcription in dinoflagellates based on previously described work.
Topics: Chromosomes; Dinoflagellida; Gene Expression Regulation; Genome; Histones
PubMed: 35447242
DOI: 10.1016/j.gene.2022.146505 -
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 -
Trends in Microbiology Apr 2021The cnidarian-dinoflagellate symbiosis is of huge importance as it underpins the success of coral reefs, yet we know very little about how the host cnidarian and its... (Review)
Review
The cnidarian-dinoflagellate symbiosis is of huge importance as it underpins the success of coral reefs, yet we know very little about how the host cnidarian and its dinoflagellate endosymbionts communicate with each other to form a functionally integrated unit. Here, we review the current knowledge of interpartner molecular signaling in this symbiosis, with an emphasis on lipids, glycans, reactive species, biogenic volatiles, and noncoding RNA. We draw upon evidence of these compounds from recent omics-based studies of cnidarian-dinoflagellate symbiosis and discuss the signaling roles that they play in other, better-studied symbioses. We then consider how improved knowledge of interpartner signaling might be used to develop solutions to the coral reef crisis by, for example, engineering more thermally resistant corals.
Topics: Animals; Coral Reefs; Dinoflagellida; Lipid Metabolism; Lipids; Signal Transduction; Symbiosis
PubMed: 33041180
DOI: 10.1016/j.tim.2020.08.005 -
Advances in Marine Biology 2022Among the most successful microeukaryotes to form mutualisms with animals are dinoflagellates in the family Symbiodiniaceae. These photosynthetic symbioses drive... (Review)
Review
Among the most successful microeukaryotes to form mutualisms with animals are dinoflagellates in the family Symbiodiniaceae. These photosynthetic symbioses drive significant primary production and are responsible for the formation of coral reef ecosystems but are particularly sensitive when environmental conditions become extreme. Annual episodes of widespread coral bleaching (disassociation of the mutualistic partnership) and mortality are forecasted from the year 2060 under current trends of ocean warming. However, host cnidarians and dinoflagellate symbionts display exceptional genetic and functional diversity, and meaningful predictions of the future that embrace this biological complexity are difficult to make. A recent move to trait-based biology (and an understanding of how traits are shaped by the environment) has been adopted to move past this problem. The aim of this review is to: (1) provide an overview of the major cnidarian lineages that are symbiotic with Symbiodiniaceae; (2) summarise the symbiodiniacean genera associated with cnidarians with reference to recent changes in taxonomy and systematics; (3) examine the knowledge gaps in Symbiodiniaceae life history from a trait-based perspective; (4) review Symbiodiniaceae trait variation along three abiotic gradients (light, nutrients, and temperature); and (5) provide recommendations for future research of Symbiodiniaceae traits. We anticipate that a detailed understanding of traits will further reveal basic knowledge of the evolution and functional diversity of these mutualisms, as well as enhance future efforts to model stability and change in ecosystems dependent on cnidarian-dinoflagellate organisms.
Topics: Animals; Anthozoa; Coral Reefs; Dinoflagellida; Ecosystem; Symbiosis
PubMed: 36208879
DOI: 10.1016/bs.amb.2022.07.001 -
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 -
Cellular Microbiology Jan 2020The ability to observe in situ 3D distribution and dynamics of endosymbionts in corals is crucial for gaining a mechanistic understanding of coral bleaching and reef...
The ability to observe in situ 3D distribution and dynamics of endosymbionts in corals is crucial for gaining a mechanistic understanding of coral bleaching and reef degradation. Here, we report the development of a tissue clearing (TC) coupled with light sheet fluorescence microscopy (LSFM) method for 3D imaging of the coral holobiont at single-cell resolution. The initial applications have demonstrated the ability of this technique to provide high spatial resolution quantitative information of endosymbiont abundance and distribution within corals. With specific fluorescent probes or assays, TC-LSFM also revealed spatial distribution and dynamics of physiological conditions (such as cell proliferation, apoptosis, and hypoxia response) in both corals and their endosymbionts. This tool is highly promising for in situ and in-depth data acquisition to illuminate coral symbiosis and health conditions in the changing marine environment, providing fundamental information for coral reef conservation and restoration.
Topics: Animals; Anthozoa; Coral Reefs; Dinoflagellida; Microscopy, Fluorescence; Symbiosis
PubMed: 31634977
DOI: 10.1111/cmi.13122