Host starvation and in hospite degradation of algal symbionts shape the heat stress response of the Cassiopea-Symbiodiniaceae symbiosis

Microbiome, Journal Year: 2024, Volume and Issue: 12(1)

Published: Feb. 29, 2024

Abstract Background Global warming is causing large-scale disruption of cnidarian-Symbiodiniaceae symbioses fundamental to major marine ecosystems, such as coral reefs. However, the mechanisms by which heat stress perturbs these symbiotic partnerships remain poorly understood. In this context, upside-down jellyfish Cassiopea has emerged a powerful experimental model system. Results We combined controlled experiment with isotope labeling and correlative SEM-NanoSIMS imaging show that host starvation central component in chain events ultimately leads collapse holobiont. Heat caused an increase catabolic activity depletion carbon reserves unfed host, concurrent reduction supply photosynthates from its algal symbionts. This state was accompanied pronounced hospite degradation symbionts, may be distinct feature response . Interestingly, loss symbionts concealed body shrinkage starving animals, resulting what could referred “invisible” bleaching. Conclusions Overall, our study highlights importance nutritional status Compared other cnidarians, large mesoglea , structural sugar protein content, constitute energy reservoir capable delaying starvation. It seems plausible anatomical at least partly contributes relatively high tolerance animals rapidly oceans.

Language: Английский

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Starvation differentially affects gene expression, immunity and pathogen susceptibility across symbiotic states in a model cnidarian

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2024, Volume and Issue: 291(2017)

Published: Feb. 28, 2024

Mutualistic symbioses between cnidarians and photosynthetic algae are modulated by complex interactions host immunity environmental conditions. Here, we investigate how symbiosis interacts with food limitation to influence gene expression stress response programming in the sea anemone Exaiptasia pallida (Aiptasia). Transcriptomic responses starvation were similar symbiotic aposymbiotic Aiptasia; however, stronger. Starved Aiptasia of both states exhibited increased protein levels immune-related transcription factor NF-κB, its associated pathways, putative target genes. However, this starvation-induced increase NF-κB correlated only anemones. Furthermore, had opposite effects on susceptibility pathogen oxidative challenges, suggesting distinct energetic priorities under scarce Finally, when compared those a facultative coral non-symbiotic anemone, ‘defence’ similarly regulated coral, but not anemone. This pattern suggests that capacity for influences immune cnidarians. In summary, certain pathways—including NF-κB—does necessarily predict pathogens, highlighting complexities cnidarian varying demands.

Language: Английский

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Exploring different methods of Exaiptasia pallida infection to follow Vibrio parahaemolyticus dissemination in the whole animal

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

Published: Feb. 16, 2024

Abstract When studying host-pathogen interactions, the method of administration pathogen is a crucial parameter to control injected dose bacteria and stress experienced by animal during manipulation. Here we developed two models infection (balneation or injection) Exaiptasia pallida (E. pallida) Vibrio parahaemolyticus expressing GFP (Vp-GFP). The injection, which provided better quantity introduced inside animal, induced response with contraction rejection bacteria. We followed Vp-GFP dissemination confocal microscopy over time at 6, 24 30 hours. During early infection, adhering ectoderm were observed in both methods. At latter disappeared from appeared gastroderm. In case located gastroderm after 6 hours, whereas balneation case, reached until methods, conclusion, using Vp-GFP, demonstrated for first that can infect E. quantified whole animals. also localized them different tissues, especially mesenterial filaments, are main entry route independently method.

Language: Английский

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