Cnidarian Immunity: From Genomes to Phenomes

Mydlarz, Laura D.; Fuess, Lauren E.; Mann, Whitney T.; Pinzón, Jorge H.; Gochfeld, Deborah J.

doi:10.1007/978-3-319-31305-4_28

Cited by 49 publications

(52 citation statements)

References 211 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…LPS is one of many virulence factors that initiates host response, primarily through activation of TLR4 in humans [74,75]. It is evident that corals possess a variety of TLR receptors, some of which are analogous to TLR4, although the variation of TLR receptors within specific species of corals is still unknown [61][62][63]. This potential diversity of TLR receptors may have contributed in part to the variation of host immune responses observed here, and therefore may have significant ecological consequences.…”

Section: Discussionmentioning

confidence: 87%

Life or death: disease-tolerant coral species activate autophagy following immune challenge

Fuess

Weil

et al. 2017

Proc. R. Soc. B.

Self Cite

View full text Add to dashboard Cite

Global climate change has increased the number and severity of stressors affecting species, yet not all species respond equally to these stressors. Organisms may employ cellular mechanisms such as apoptosis and autophagy in responding to stressful events. These two pathways are often mutually exclusive, dictating whether a cell adapts or dies. In order to examine differences in cellular response to stress, we compared the immune response of four coral species with a range of disease susceptibility. Using RNA-seq and novel pathway analysis, we were able to identify differences in response to immune stimulation between these species. Disease-susceptible species activated pathways associated with apoptosis. By contrast, disease-tolerant species and activated autophagic pathways. Moderately susceptible species activated a mixture of these pathways. These findings were corroborated by apoptotic caspase protein assays, which indicated increased caspase activity following immune stimulation in susceptible species. Our results indicate that in response to immune stress, disease-tolerant species activate cellular adaptive mechanisms such as autophagy, while susceptible species turn on cell death pathways. Differences in these cellular maintenance pathways may therefore influence the organismal stress response. Further study of these pathways will increase understanding of differential stress response and species survival in the face of changing environments.

show abstract

Section: Discussionmentioning

confidence: 87%

Life or death: disease-tolerant coral species activate autophagy following immune challenge

Fuess

Weil

et al. 2017

Proc. R. Soc. B.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Corals are sedentary, multipartite organisms that have evolved complex, integrated physiological systems to survive fluctuations in local environmental conditions, predation and disease (e.g., Miller et al, 2007;Palmer and Traylor-Knowles, 2012;Mydlarz et al, 2016). As such, differing immune strategies have likely evolved among corals to maintain optimal fitness while mitigating the energetic and autoimmune costs in upregulating an immune response (Palmer et al, 2010(Palmer et al, , 2011c.…”

Section: Introductionmentioning

confidence: 99%

Warmer Water Affects Immunity of a Tolerant Reef Coral

Palmer

2018

Front. Mar. Sci.

View full text Add to dashboard Cite

Corals are multipartite sedentary organisms, which have evolved complex, physiological networks in order to survive perturbations and environmental fluctuations. However, climate change is warming tropical waters, pushing the limits of coral tolerance and driving global declines. Coral susceptibility to thermal anomalies is variable among species and through time, and directly relates to constituent immunity. Constituent immunity refers to immune activities required to ensure homeostasis, whereas an immune response is acutely heightened immune activity to a perturbation. Understanding the mechanisms behind coral health, and sustained health through adverse conditions, is increasingly important for establishing effective reef conservation and restoration projects. However, most experimental studies of coral health use species that are highly susceptible to thermal events, potentially skewing our understanding. To determine the influence of warmer water on immunity, activities of key coral immune pathways and an antioxidant were compared under ambient (27 • C) and warmer water (32 • C), and between injured and uninjured (control) branches of the tolerant reef coral Porites cylindrica. Three types of phenoloxidase, mono-phenoloxidase, ortho-diphenoloxidase and para-diphenloxidase, indicative of two melanin synthesis pathways (the tyrosinase and laccase-type), and peroxidase were measured at 0 (control), 1, 6, 24, 48, and 168 h post-injury. All four enzymes demonstrated consistent levels of activity under ambient conditions (27 • C), indicating constituent immunity. Upon injury at ambient temperature, all enzyme activities were significantly higher 1 h post-injury as compared to uninjured controls, demonstrating a comprehensive immune response to tissue disruption. Under warmer water, constituent immunity increased through time indicative of immune modulation to maintain homeostasis. However, warmer water, within the non-bleaching summer range, suppressed the immune response to injury, delaying it by 24 h. Therefore, upon the environmental cue of warmer water, the tolerant coral P. cylindrica may divert resources away from immune responses (immunosuppression) while enhancing constituent immunity (immune modulation) so as to maintain health through sub-optimal conditions. These changes in immunity with warmer water demonstrate that temperature affects coral immunity and, for this tolerant coral, triggers immune-modulation that may provide cross-tolerance to perturbations more frequent in summer months, such as bleaching and disease.

show abstract

“…While caspases from human cells, and model organisms such as C. elegans and Drosophila, have been well-studied both biochemically and structurally (1-6), little is known about caspase activity and regulation from other species (7). Invertebrate caspases were first characterized in C. elegans (3,6) and Drosophila (8), but they have proven to be poor models for studying the evolution of the vertebrate apoptotic network as the networks in C. elegans and in Drosophila utilize fewer caspases and regulatory proteins compared to higher eukaryotes. In contrast, vertebrates have retained many characteristics of the apoptotic machinery found in sponges, sea anemone, and coral (9)(10)(11).…”

Section: Introductionmentioning

confidence: 99%

“…Disease susceptibility is one of several major stressors of coral communities, with over thirty-five coral diseases reported that affect over eighty coral species (8,15). Coral possess a rudimentary immune system that consists of innate immune pathways but no adaptive immune system (16).…”

Section: Introductionmentioning

confidence: 99%

Caspases from Scleractinian Coral Show Unique Regulatory Features

Shrestha

Tung

Grinshpon

et al. 2020

Preprint

View full text Add to dashboard Cite

Diseases affecting coral have led to massive decline and altered the community structure of reefs. In response to immune challenges, cnidaria activate apoptotic or autophagic pathways, and the particular pathway correlates with disease sensitivity (apoptosis) or resistance (autophagy).Although cnidaria contain complex apoptotic signaling pathways, similar to those in vertebrates, the mechanisms leading to cell death are largely unexplored. We identified and characterized two caspases each from Orbicella faveolata, a disease-sensitive stony coral, and Porites astreoides, a disease-resistant stony coral. The four caspases are predicted homologs of human caspases-3 and -7, but OfCasp3a and PaCasp7a contain an amino-terminal caspase activation and recruitment domain (CARD) similar to human initiator/inflammatory caspases. In contrast, OfCasp3b and PaCasp3 have short pro-domains, like human effector caspases. We show that OfCasp3a and PaCasp7a are DxxDases, like human caspases-3 and -7, while OfCasp3b and PaCasp3 are more similar to human caspase-6, with VxxDase activity. Our biochemical analyses suggest a mechanism in coral in which the CARD-containing DxxDase is activated on death platforms, but the protease does not directly activate the VxxDase. We also report the first X-ray crystal structure of a coral caspase, that of PaCasp7a determined at 1.57Å resolution. The structure reveals overall conservation of the caspase-hemoglobinase fold in coral as well as an N-terminal peptide bound near the active site that may serve as a regulatory exosite. The binding pocket has been observed in initiator caspases of other species, suggesting mechanisms for the evolution of substrate selection while maintaining common activation mechanisms of CARD-mediated dimerization.P. astreoides and O. faveolata contain VxxDases similar to HsCasp6. Our data show that the enzymes from both species have similar biochemical properties and are activated by similar mechanisms. Together, the data show that the role of the caspase cascade in disease resistance of P. astreoides or in disease sensitivity of O. faveolata may derive from differences in response mechanisms in the death receptor or the PIDDosome activation platforms, that is, signaling events upstream of the caspase cascade. Since the caspases in the two species exhibit similar biochemical properties and activation mechanisms, our data suggest that differences in the receptor-mediated activation of caspases as well as cross-talk between the autophagic and apoptotic pathways in the two coral species lead to the different physiological responses.

show abstract

Cnidarian Immunity: From Genomes to Phenomes

Cited by 49 publications

References 211 publications

Life or death: disease-tolerant coral species activate autophagy following immune challenge

Life or death: disease-tolerant coral species activate autophagy following immune challenge

Warmer Water Affects Immunity of a Tolerant Reef Coral

Caspases from Scleractinian Coral Show Unique Regulatory Features

Contact Info

Product

Resources

About