Molecular insights into the Darwin paradox of coral reefs from the sea anemone Aiptasia

Science Advances, Journal Year: 2023, Volume and Issue: 9(11)

Published: March 15, 2023

Symbiotic cnidarians such as corals and anemones form highly productive biodiverse coral reef ecosystems in nutrient-poor ocean environments, a phenomenon known Darwin's paradox. Resolving this paradox requires elucidating the molecular bases of efficient nutrient distribution recycling cnidarian-dinoflagellate symbiosis. Using sea anemone Aiptasia, we show that during symbiosis, increased availability glucose presence algae jointly induce coordinated up-regulation relocalization ammonium transporters. These responses are critical to support symbiont functioning organism-wide nitrogen assimilation through glutamine synthetase/glutamate synthase-mediated amino acid biosynthesis. Our results reveal crucial aspects mechanisms underlying conservation these organisms allow them thrive nitrogen-poor environments.

Language: Английский

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Symbiotic dinoflagellates divert energy away from mutualism during coral bleaching recovery

Symbiosis, Journal Year: 2023, Volume and Issue: 89(2), P. 173 - 186

Published: Jan. 28, 2023

Language: Английский

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A carbon-nitrogen negative feedback loop underlies the repeated evolution of cnidarian–Symbiodiniaceae symbioses

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Nov. 1, 2023

Symbiotic associations with Symbiodiniaceae have evolved independently across a diverse range of cnidarian taxa including reef-building corals, sea anemones, and jellyfish, yet the molecular mechanisms underlying their regulation repeated evolution are still elusive. Here, we show that despite independent evolution, hosts use same carbon-nitrogen negative feedback loop to control symbiont proliferation. Symbiont-derived photosynthates used assimilate nitrogenous waste via glutamine synthetase-glutamate synthase-mediated amino acid biosynthesis in carbon-dependent manner, which regulates availability nitrogen symbionts. Using nutrient supplementation experiments, provision additional carbohydrates significantly reduces density while ammonium promotes High-resolution metabolic analysis confirmed all co-incorporated glucose-derived 13C ammonium-derived 15N biosynthesis. Our results reveal general these symbioses provide parsimonious explanation for evolution.

Language: Английский

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Ocean acidification alters foraging behaviour in Dungeness crab through impairment of the olfactory pathway

Global Change Biology, Journal Year: 2023, Volume and Issue: 29(14), P. 4126 - 4139

Published: May 9, 2023

Crustacean olfaction is fundamental to most aspects of living and communicating in aquatic environments more broadly, for individual- population-level success. Accelerated ocean acidification from elevated CO2 threatens the ability crabs detect respond important olfactory-related cues. Here, we demonstrate that ecologically economically Dungeness crab (Metacarcinus magister) exhibits reduced antennular flicking responses a food cue when exposed near-future levels, adding growing body evidence impaired behaviour. Underlying this altered behaviour, find have lower olfactory nerve sensitivities (twofold reduction activity) response . This suggests levels will impact threshold detection by crabs. We also show sensitivity accompanied decrease sensory neuron (OSN) expression principal chemosensory receptor protein, ionotropic 25a (IR25a) which odorant coding signalling cascades. The OSNs exhibit morphological changes form decreased surface areas their somata. study provides first effects high at multiple biological organization marine crabs, linking physiological cellular with whole animal behavioural responses.

Language: Английский

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Insights into the molecular mechanisms underlying the different heat tolerance of the scleractinian coral Pavona decussata

Coral Reefs, Journal Year: 2024, Volume and Issue: 43(2), P. 429 - 442

Published: March 4, 2024

Language: Английский

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Synergistic/antagonistic effects of nitrate/ammonium enrichment on fatty acid biosynthesis and translocation in coral under heat stress

The Science of The Total Environment, Journal Year: 2023, Volume and Issue: 876, P. 162834 - 162834

Published: March 15, 2023

Language: Английский

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pH regulation in coral photosymbiosis and calcification: a compartmental perspective

New Phytologist, Journal Year: 2025, Volume and Issue: unknown

Published: May 14, 2025

Summary The coral‐dinoflagellate photosymbiosis and coral calcification underpin shallow water, reef ecosystems. This review examines the pivotal role of pH regulation in cell physiology these processes. Despite simple tissue organization, photosymbiotic corals maintain a complex internal microenvironment, with distinct compartments exhibiting contrasting levels. For example, acidic ‘symbiosome’ surrounds algal symbionts, while alkaline ‘extracellular calcifying medium’ occurs at growing front skeleton. We discuss how is crucial to functioning calcification, as well mitigating acid–base imbalances that processes create. interplay between also discussed, focusing on influence symbiont photosynthesis transepithelial gradients distribution energy sources colony. Throughout this review, insights into derived from previous research ocean acidification are integrated deepen understanding. Finally, we propose priorities advance knowledge resilience under changing conditions, such investigating inorganic carbon concentration within compartments, species‐specific differences impacts thermal stress regulation.

Language: Английский

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Symbiont dynamics and coral regulation under changing temperatures

Coral Reefs, Journal Year: 2025, Volume and Issue: unknown

Published: May 25, 2025

Language: Английский

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Host nutrient sensing is mediated by mTOR signaling in cnidarian-dinoflagellate symbiosis

Current Biology, Journal Year: 2023, Volume and Issue: 33(17), P. 3634 - 3647.e5

Published: Aug. 11, 2023

To survive in the nutrient-poor waters of tropics, reef-building corals rely on intracellular, photosynthetic dinoflagellate symbionts. Photosynthates produced by symbiont are translocated to host, and this enables form structural foundation most biodiverse all marine ecosystems. Although regulation nutrient exchange between partners is critical for ecosystem stability health, mechanisms governing how nutrients sensed, transferred, integrated into host cell processes largely unknown. Ubiquitous among eukaryotes, mechanistic target rapamycin (mTOR) signaling pathway integrates intracellular extracellular stimuli influence growth cell-cycle progression balance metabolic processes. A functional role mTOR integration was demonstrated various nutritional symbioses, a similar proposed coral-algal symbioses. Using endosymbiosis model Aiptasia, we examined both larvae adult polyps across stages symbiosis. We found that symbiosis enhances proliferation, using an Aiptasia-specific antibody, localized symbiosome membranes. activated symbiosis, while inhibition disrupts niche establishment altogether. Additionally, observed dysbiosis conserved response coral species. Our data confim plays pivotal integrating symbiont-derived metabolism stability, ultimately allowing symbiotic cnidarians thrive challenging environments.

Language: Английский

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Branchial CO₂ and ammonia excretion in crustaceans: Involvement of an apical Rhesus‐like glycoprotein

Acta Physiologica, Journal Year: 2024, Volume and Issue: 240(2)

Published: Jan. 11, 2024

Abstract Aim To determine whether the crustacean Rh1 protein functions as a dual CO 2 /ammonia transporter and investigate its role in branchial ammonia excretion acid–base regulation. Methods Sequence analysis of decapod proteins was used to conservation amino acid residues putatively involved transport binding human bacterial Rh proteins. Using Carcinus maenas (CmRh1) representative proteins, we test capabilities CmRh1 through heterologous expression yeast Xenopus oocytes coupled with site‐directed mutagenesis. Quantitative PCR assess distribution mRNA various tissues. Western blotting changes response high environmental . Further, immunohistochemistry sub‐cellular localization membrane‐bound carbonic anhydrase (CmCAg). Results revealed several conducting binding. Expression enhanced both which nullified D180N mutant oocytes. Transport analog methylamine by is dependent on ionized un‐ionized ammonia/methylamine species. co‐localized CmCAg apical membrane gill only experienced decreased anterior gills when exposed ammonia. Conclusion first identified transporter‐mediated route for gill. Our findings shed further light potential universality capacity Rhesus glycoproteins vertebrates invertebrates.

Language: Английский

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