Signaling pathways of heat- and hypersalinity-induced polyp bailout in Pocillopora acuta

AbstractPolyp bailout is a drastic response to acute stress where coral coloniality breaks down and polyps detach. We induced polyp bailout in Pocillopora acuta with heat stress and tested for differential gene expression using RNAseq and a qPCR assay. Furthermore, we induced polyp bailout with hypersalinity and compared the results to identify stressor-independent signals and pathways active during polyp bailout. Both stressors led to the onset of polyp bailout and the detachment of vital polyps. We observed activation of microbe-associated molecular pattern receptors and downstream signaling pathways of the innate immune system. Further, we detected growth factors and genes active during Wnt-signaling potentially contributing to wound healing, regeneration, and proliferation. Upregulation of several genes encoding for matrix metalloproteinases and the fibroblast growth factor signaling pathway are the most likely involved in the remodeling of the extracellular matrix, as well as in the detachment of polyps from the calcareous skeleton during polyp bailout. Expression of genes of interest in our qPCR assay of vital polyps from our heat-stress experiment, showed a trend for a normalization of gene expression after polyp bailout. Our results provide new insights into the signaling cascades leading to the observed physiological responses during polyp bailout. Comparison between the two stressors showed that certain signaling pathways are independent of the stressor and suggested that polyp bailout is a general response of corals to acute stress. Furthermore, immune system responses during polyp bailout indicate that microbe-associated partners of corals may lead to the polyp bailout response.

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Immunoregulatory Property of C-Type Lectin-Like Receptors in Fibrosing Interstitial Lung Diseases

International Journal of Molecular Sciences ◽

10.3390/ijms21103665 ◽

2020 ◽

Vol 21 (10) ◽

pp. 3665

Author(s):

Wiwin Is Effendi ◽

Tatsuya Nagano ◽

Helmia Hasan ◽

Resti Yudhawati

Keyword(s):

Immune System ◽

Signaling Pathways ◽

Intracellular Signaling ◽

Lung Diseases ◽

Wound Repair ◽

Tissue Injury ◽

Interstitial Lung Diseases ◽

Downstream Signaling ◽

Cytokine Activation ◽

Immune Impairment

The innate immune system identifies exogenous threats or endogenous stress through germline-encoded receptors called pattern recognition receptors (PRRs) that initiate consecutive downstream signaling pathways to control immune responses. However, the contribution of the immune system and inflammation to fibrosing interstitial lung diseases (ILD) remains poorly understood. Immunoreceptor tyrosine-based motif-bearing C-type lectin-like receptors (CTLRs) may interact with various immune cells during tissue injury and wound repair processes. Dectin-1 is a CTLR with dominant mechanisms manifested through its intracellular signaling cascades, which regulate fibrosis-promoting properties through gene transcription and cytokine activation. Additionally, immune impairment in ILD facilitates microbiome colonization; hence, Dectin-1 is the master protector in host pulmonary defense against fungal invasion. Recent progress in determining the signaling pathways that control the balance of fibrosis has implicated immunoreceptor tyrosine-based motif-bearing CTLRs as being involved, either directly or indirectly, in the pathogenesis of fibrosing ILD.

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The genetics of sleep

10.1093/med/9780199682003.003.0005 ◽

2017 ◽

Author(s):

Alexandra Sousek ◽

Mehdi Tafti

Keyword(s):

Gene Expression ◽

Immune System ◽

Signaling Pathways ◽

Strong Evidence ◽

Sleep Loss ◽

Genetic Variations ◽

Genetic Contribution ◽

Individual Pattern ◽

Individual Variations ◽

The Individual

Although there is strong evidence for a genetic contribution to inter-individual variations in sleep, the underlying factors and their interaction remain largely elusive. Much effort has been expended in studying genetic variations contributing to circadian and sleep phenotypes, the individual pattern of the human sleep EEG, reactions to sleep loss, and the pathophysiology of sleep-related disorders. Certain sleep-related diseases may be caused by single genes, while the etiology of others seems to be variable and complex. This is especially the case when the immune system is involved. This chapter reports on twin and familial studies, genetic variations and mutations affecting neurotransmitters and other signaling pathways and thereby affecting sleep, and impacts of gene expression processes and the immune system on sleep. Although much knowledge has been gained, further research is needed to elucidate the all-embracing mechanisms and their interactions that regulate sleep.

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Insulin-Like Peptide Receptor-Mediated Signaling Pathways Orchestrate Regulation of Growth in the Pacific Oyster (Crassostrea gigas), as Revealed by Gene Expression Profiles

International Journal of Molecular Sciences ◽

10.3390/ijms22105259 ◽

2021 ◽

Vol 22 (10) ◽

pp. 5259

Author(s):

Yongjing Li ◽

Huiru Fu ◽

Fuqiang Zhang ◽

Liting Ren ◽

Jing Tian ◽

...

Keyword(s):

Signaling Pathways ◽

Signaling Pathway ◽

Crassostrea Gigas ◽

Growth Regulation ◽

Pacific Oyster ◽

Expression Profiles ◽

Growth Factor Signaling ◽

Bioinformatics Analyses ◽

Peptide Receptor ◽

Downstream Signaling

The involvement of insulin/insulin-like growth factor signaling (IIS) pathways in the growth regulation of marine invertebrates remains largely unexplored. In this study, we used a fast-growing Pacific oyster (Crassostrea gigas) variety “Haida No.1” as the material with which to unravel the role of IIS systems in growth regulation in oysters. Systematic bioinformatics analyses allowed us to identify major components of the IIS signaling pathway and insulin-like peptide receptor (ILPR)-mediated signaling pathways, including PI3K-AKT, RAS-MAPK, and TOR, in C. gigas. The expression levels of the major genes in IIS and its downstream signaling pathways were significantly higher in “Haida No.1” than in wild oysters, suggesting their involvement in the growth regulation of C. gigas. The expression profiles of IIS and its downstream signaling pathway genes were significantly altered by nutrient abundance and culture temperature. These results suggest that the IIS signaling pathway coupled with the ILPR-mediated signaling pathways orchestrate the regulation of energy metabolism to control growth in Pacific oysters.

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Structural aspects of molecular recognition in the immune system. Part II: Pattern recognition receptors (IUPAC Technical Report)

Pure and Applied Chemistry ◽

10.1515/pac-2013-1026 ◽

2014 ◽

Vol 86 (10) ◽

pp. 1483-1538 ◽

Cited By ~ 4

Author(s):

John A. Robinson ◽

Kerstin Moehle

Keyword(s):

Pattern Recognition ◽

Immune System ◽

Immune Responses ◽

Signaling Pathways ◽

Innate Immune System ◽

Pattern Recognition Receptors ◽

Innate Immune ◽

Helicase Domain ◽

Downstream Signaling ◽

Adaptive Immune

Abstract The vertebrate immune system uses pattern recognition receptors (PRRs) to detect a large variety of molecular signatures (pathogen-associated molecular patterns, PAMPs) from a broad range of different invading pathogens. The PAMPs range in size from relatively small molecules, to others of intermediate size such as bacterial lipopolysaccharide, lipopeptides, and oligosaccharides, to macromolecules such as viral DNA, RNA, and pathogen-derived proteins such as flagellin. Underlying this functional diversity of PRRs is a surprisingly small number of structurally distinct protein folds that include leucine-rich repeats in Toll-like receptors (TLRs) and NOD-like receptors (NLRs), the DExH box helicase domain in RIG-like receptors (RLRs), and C-type lectin domains (CTLDs) in the C-type lectins. Following PAMP recognition by the PRRs, downstream signaling pathways activate the innate immune system to respond to invading pathogenic organisms. The resulting stimulatory response is also vital for a balanced adaptive immune response to the pathogen, mediated by circulating antibodies and/or cytotoxic T cells. However, an aberrant stimulation of the innate immune system can also lead to excessive inflammatory and toxic stress responses. Exciting opportunities are now arising for the design of small synthetic molecules that bind to PRRs and influence downstream signaling pathways. Such molecules can be useful tools to modulate immune responses, for example, as adjuvants to stimulate adaptive immune responses to a vaccine, or as therapeutic agents to dampen aberrant immune responses, such as inflammation. The design of agonists or antagonists of PRRs can now benefit from a surge in knowledge of the 3D structures of PRRs, many in complexes with their natural ligands. This review article describes recent progress in structural studies of PRRs (TLRs, NLRs, CTLs, and RLRs), which is required for an understanding of how they specifically recognize structurally diverse “foreign” PAMPs amongst a background of other “self” molecules, sometimes closely related in structure, that are present in the human body.

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MOTHER-OF-FT-AND-TFL1 represses seed germination under far-red light by modulating phytohormone responses in Arabidopsis thaliana

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1806460115 ◽

2018 ◽

Vol 115 (33) ◽

pp. 8442-8447 ◽

Cited By ~ 20

Author(s):

Fabián E. Vaistij ◽

Thiago Barros-Galvão ◽

Adama F. Cole ◽

Alison D. Gilday ◽

Zhesi He ◽

...

Keyword(s):

Gene Expression ◽

Transcription Factor ◽

Seed Germination ◽

Signaling Pathways ◽

Red Light ◽

Dependent Manner ◽

Light Conditions ◽

Ga Signaling ◽

Expression Of Genes ◽

Genes Encoding

Seed germination in many plant species is triggered by sunlight, which is rich in the red (R) wavelength and repressed by under-the-canopy light rich in far red (FR). R:FR ratios are sensed by phytochromes to regulate levels of gibberellins (GAs) and abscisic acid (ABA), which induce and inhibit germination respectively. In this study we have discovered that, under FR light conditions, germination is repressed by MOTHER-OF-FT-AND-TFL1 (MFT) through the regulation of the ABA and GA signaling pathways. We also show that MFT gene expression is tightly regulated by light quality. Previous work has shown that under FR light conditions the transcription factor PHYOCHROME-INTERACTING-FACTOR1 (PIF1) accumulates and promotes expression of SOMNUS (SOM) that, in turn, leads to increased ABA and decreased GA levels. PIF1 also promotes expression of genes encoding ABA-INSENSITIVE5 (ABI5) and DELLA growth-repressor proteins, which act in the ABA and GA signaling pathways, respectively. Here we show that MFT gene expression is promoted by FR light through the PIF1/SOM/ABI5/DELLA pathway and is repressed by R light via the transcription factor SPATULA (SPT). Consistent with this, we also show that SPT gene expression is repressed under FR light in a PIF1-dependent manner. Furthermore, transcriptomic analyses presented in this study indicate that MFT exerts its function by promoting expression of known ABA-induced genes and repressing cell wall expansion-related genes.

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Patterns of thermotolerance, chlorophyll fluorescence, and heat shock gene expression vary among four Boechera species and Arabidopsis thaliana

Botany ◽

10.1139/cjb-2016-0158 ◽

2017 ◽

Vol 95 (1) ◽

pp. 9-27 ◽

Cited By ~ 5

Author(s):

Gillian Halter ◽

Nicole Simonetti ◽

Cristy Suguitan ◽

Kenneth Helm ◽

Jessica Soroksky ◽

...

Keyword(s):

Gene Expression ◽

Arabidopsis Thaliana ◽

Heat Stress ◽

Chlorophyll Fluorescence ◽

Heat Shock ◽

Leaf Damage ◽

Wild Plant ◽

Heat Shock Gene ◽

Acquired Thermotolerance ◽

Genes Encoding

Thermotolerance is a property of all organisms, but owing to their sessile nature, this trait is particularly important in plants. Basal thermotolerance is based on inherent tolerance to heat stress. Acquired thermotolerance is attained through stress-induced gene expression, often of those genes encoding heat shock proteins (HSPs). Both basal and acquired thermotolerance have been extensively studied in model species such as Arabidopsis thaliana (L.) Heynh., but much less is known about thermotolerance in wild plant species. The aims of this study were to examine the basal and acquired thermotolerance of four species of Boechera, and of A. thaliana. Four species of Boechera native to California were collected and used for this study: B. arcuata (Nutt.) Windham & Al-Shehbaz, B. californica (Rollins) Windham & Al-Shehbaz, B. depauperata (A.Nelson & P.B.Kenn.) Windham & Al-Shehbaz, and B. perennans (S.Watson) W.A.Weber. Seedlings were exposed to both basal and acquired heat stress and then monitored for leaf damage, chlorophyll fluorescence, and gene expression of HsfA3, Hsp101, and four sHSP genes. Analysis of organismal responses to heat stress demonstrated that all four Boechera species are more thermotolerant than A. thaliana. Further we found that he species with the highest thermotolerance is B. depauperata.

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Transcriptional response of skeletal muscle to a low-protein gestation diet in porcine offspring accumulates in growth- and cell cycle-regulating pathways

Physiological Genomics ◽

10.1152/physiolgenomics.00050.2012 ◽

2012 ◽

Vol 44 (16) ◽

pp. 811-818 ◽

Cited By ~ 8

Author(s):

Michael Oster ◽

Eduard Murani ◽

Cornelia C. Metges ◽

Siriluck Ponsuksili ◽

Klaus Wimmers

Keyword(s):

Gene Expression ◽

Cell Cycle ◽

Skeletal Muscle ◽

Signaling Pathways ◽

Cell Cycle Regulation ◽

Acid Metabolism ◽

Energy Utilization ◽

Nucleic Acid Metabolism ◽

Growth Factor Signaling ◽

Cycle Regulation

Inadequate maternal protein supply during gestation represents an environmental factor that affects physiological signaling pathways with long-term consequences for growth, function, and structure of various tissues. Hypothesizing that the offspring's transcriptome is persistently altered by maternal diets, we used a porcine model to monitor the longitudinal expression changes in muscle to identify pathways relevant to fetal initiation of postnatal growth and development. German Landrace gilts were fed isoenergetic gestational diets containing 6.5% (LP) or 12.1% protein. The longissimus dorsi samples were collected from offspring at 94 days postconception (dpc) and 1, 28, and 188 days postnatum (dpn) for expression profiling. At 94 dpc, 1 dpn, and 28 dpn relatively few transcripts (<130) showed an altered abundance between the dietary groups. In fact, at 94 dpc genes of G2/M checkpoint regulation and mitotic roles of Polo-like kinases showed lowered transcript abundance in LP. At 188 dpn 677 transcripts were altered including those related to oxidative phosphorylation, citrate cycle, fatty acid metabolism (higher abundance in LP) and cell cycle regulation (lower abundance in LP). Correspondingly, transcriptional alterations during pre and postnatal development differed considerably among dietary groups, particularly for genes related to cell cycle regulation (G1/S and G2/M checkpoint regulation; cyclines), growth factor signaling (GH, IGF1, mTOR, RAN, VEGF, INSR), lipid metabolism, energy metabolism, and nucleic acid metabolism. In skeletal muscle, fetal programming related to maternal LP diets disturbed gene expression in growth-related pathways into adulthood. Diet-dependent gene expression may hamper proper development, thereby affecting signaling pathways related to energy utilization.

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