A regulatory interface on RIPK2 is required for XIAP binding and NOD signaling activity

AbstractSignaling via the intracellular pathogen receptors Nucleotide-binding oligomerization domain-containing proteins NOD1 and NOD2 requires Receptor Interacting Kinase 2 (RIPK2), an adaptor kinase that can be targeted for the treatment of various inflammatory diseases. However, the molecular mechanisms of how RIPK2 contributes to NOD signaling are not completely understood. We generated FLAG-tagged RIPK2 knock-in mice using CRISPR/Cas9 technology to study NOD signaling mechanisms at the endogenous level. Using cells from these mice we were able to generate a detailed map of post-translational modifications on RIPK2 during NOD signaling and we identified a new regulatory interface on RIPK2, which dictates the crucial interaction with the E3 ligase XIAP.

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Mutational analysis of human NOD1 and NOD2 NACHT domains reveals different modes of activation

Innate Immunity ◽

10.1177/1753425910394002 ◽

2011 ◽

Vol 18 (1) ◽

pp. 100-111 ◽

Cited By ~ 50

Author(s):

Birte Zurek ◽

Martina Proell ◽

Roland N Wagner ◽

Robert Schwarzenbacher ◽

Thomas A Kufer

Keyword(s):

Atp Hydrolysis ◽

Mutational Analysis ◽

Inflammatory Diseases ◽

Nucleotide Binding ◽

Blau Syndrome ◽

Innate Immune Responses ◽

Atpase Domain ◽

Early Onset Sarcoidosis ◽

Key Residues ◽

Oligomerization Domain

Nucleotide-binding oligomerization domain-containing protein (NOD)1 and NOD2 are intracellular pattern recognition receptors (PRRs) of the nucleotide-binding domain and leucine-rich repeat containing (NLR) gene family involved in innate immune responses. Their centrally located NACHT domain displays ATPase activity and is necessary for activation and oligomerization leading to inflammatory signaling responses. Mutations affecting key residues of the ATPase domain of NOD2 are linked to severe auto-inflammatory diseases, such as Blau syndrome and early-onset sarcoidosis. By mutational dissection of the ATPase domain function, we show that the NLR-specific extended Walker B box (DGhDE) can functionally replace the canonical Walker B sequence (DDhWD) found in other ATPases. A requirement for an intact Walker A box and the magnesium-co-ordinating aspartate of the classical Walker B box suggest that an initial ATP hydrolysis step is necessary for activation of both NOD1 and NOD2. In contrast, a Blau-syndrome associated mutation located in the extended Walker B box of NOD2 that results in higher autoactivation and ligand-induced signaling does not affect NOD1 function. Moreover, mutation of a conserved histidine in the NACHT domain also has contrasting effects on NOD1 and NOD2 mediated NF-κB activation. We conclude that these two NLRs employ different modes of activation and propose distinct models for activation of NOD1 and NOD2.

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Nucleotide-Binding Oligomerization Domain-Like Receptor 3 Inflammasome Inhibition by MCC950 Reduces the Lipopolysaccharide-Induced Interleukin-1β in Cultured Dispersed Nasal Polyp Cells

Korean Journal of Otorhinolaryngology - Head and Neck Surgery ◽

10.3342/kjorl-hns.2019.00738 ◽

2020 ◽

Vol 63 (5) ◽

pp. 206-215

Author(s):

Soo Kyoung Park ◽

Rui-Ning Han ◽

Jun Xu ◽

Sun Hee Yeon ◽

Sung Bok Lee ◽

...

Keyword(s):

Chronic Rhinosinusitis ◽

Nasal Polyp ◽

Nlrp3 Inflammasome ◽

Nasal Polyps ◽

Inflammatory Diseases ◽

Nucleotide Binding ◽

Enzyme Linked Immunosorbent Assay ◽

Control Group ◽

Western Blot Assay ◽

Oligomerization Domain

Background and Objectives The nucleotide-binding oligomerization domain-like receptor (NLRP) 3 is known as a member of the NLR family, and it has been confirmed that the NLRP3 inflammasome is associated with various diseases such as asthma, inflammatory bowel disease, metabolic disorders and multiple sclerosis, as well as other auto-immune and auto-inflammatory diseases. However, the role of NLRP3 in chronic rhinosinusitis with nasal polyps (CRSwNP) has not yet been explored.Subjects and Method Forty-four specimens of nasal polyps and 25 specimens of uncinate processes were collected from patients with chronic rhinosinusitis with nasal polyps, and 25 specimens of uncinate tissues were collected from patients who underwent other rhino-surgeries. The western blot assay was employed to analyze the expression of NLRP3; interleukin (IL)-1β and IL-17A were detected using immunohistochemistry and real-time polymerase chain reaction. The production of lipopolysaccharide (LPS) induced IL-1β and IL-17A with or without the NLRP3 inflammasome inhibitor (MCC950) was measured using an enzyme linked immunosorbent assay in cultured dispersed nasal polyp cells.Results NLRP3 showed a high level of expression in nasal polyps than in the control group (p<0.01). The expression of IL-1β and IL-17A was significantly higher in nasal polyps in the CRSwNP group than in the control group (p<0.05). LPS-induced production of IL-1β was significantly suppressed by treatment with the NLRP3 inflammasome inhibitor (p<0.05).Conclusion The NLRP3 inflammasome plays an essential role in the pathogenesis of CRSwNP, and thus MCC950 can be considered a prospective therapeutic for NLRP3 inflammasome-mediated inflammation in nasal polyps. Our data provide new evidence that IL-17A is involved in inflammasome-associated inflammation in nasal polyps.

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Roles of NOD1 (NLRC1) and NOD2 (NLRC2) in innate immunity and inflammatory diseases

Bioscience Reports ◽

10.1042/bsr20120055 ◽

2012 ◽

Vol 32 (6) ◽

pp. 597-608 ◽

Cited By ~ 83

Author(s):

Ricardo G. Correa ◽

Snezana Milutinovic ◽

John C. Reed

Keyword(s):

Tissue Injury ◽

Inflammatory Diseases ◽

Nucleotide Binding ◽

Nuclear Factor Κb ◽

Inflammatory Disorders ◽

Genes Encoding ◽

Transduction Mechanisms ◽

Microbial Sensors ◽

Experimental Findings ◽

Oligomerization Domain

NOD1 {nucleotide-binding oligomerization domain 1; NLRC [NOD-LRR (leucine-rich repeat) family with CARD (caspase recruitment domain) 1]} and NOD2 (NLRC2) are among the most prominent members of the NLR (NOD-LRR) family –proteins that contain nucleotide-binding NACHT domains and receptor-like LRR domains. With over 20 members identified in humans, NLRs represent important components of the mammalian innate immune system, serving as intracellular receptors for pathogens and for endogenous molecules elaborated by tissue injury. NOD1 and NOD2 proteins operate as microbial sensors through the recognition of specific PG (peptidoglycan) constituents of bacteria. Upon activation, these NLR family members initiate signal transduction mechanisms that include stimulation of NF-κB (nuclear factor-κB), stress kinases, IRFs (interferon regulatory factors) and autophagy. Hereditary polymorphisms in the genes encoding NOD1 and NOD2 have been associated with an increasing number of chronic inflammatory diseases. In fact, potential roles for NOD1 and NOD2 in inflammatory disorders have been revealed by investigations using a series of animal models. In the present review, we describe recent experimental findings associating NOD1 and NOD2 with various autoimmune and chronic inflammatory disorders, and we discuss prospects for development of novel therapeutics targeting these NLR family proteins.

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Applying Peptide and Protein Synthesis to Study Post-translational Modifications in Epigenetics and Beyond

CHIMIA International Journal for Chemistry ◽

10.2533/chimia.2021.484 ◽

2021 ◽

Vol 75 (6) ◽

pp. 484-488

Author(s):

Beat Fierz

Keyword(s):

Protein Synthesis ◽

Synthetic Peptide ◽

Chemical Biology ◽

Molecular Mechanisms ◽

Regulatory Mechanisms ◽

Protein Chemistry ◽

Post Translational Modifications ◽

Signaling Mechanisms ◽

Nucleoprotein Complex ◽

Gene Regulatory

Epigenetics research focuses on the study of heritable gene regulatory mechanisms that do not involve changes of the DNA sequence. Such mechanisms include post-translational modifications of histone proteins that organize the genome in the nucleus into a nucleoprotein complex called chromatin, and which are of key importance in development and disease. Chemical biology tools as developed by my group, in particular synthetic peptide and protein chemistry, have been critical to elucidate epigenetic signaling mechanisms. As outlined below, they allow the reconstitution of chromatin carrying defined modifications and thus the elucidation of detailed molecular mechanisms.

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Natural Products for Regulating Macrophages M2 Polarization

Current Stem Cell Research & Therapy ◽

10.2174/1574888x14666190523093535 ◽

2020 ◽

Vol 15 (7) ◽

pp. 559-569 ◽

Cited By ~ 1

Author(s):

Zhen Chang ◽

Youhan Wang ◽

Chang Liu ◽

Wanli Smith ◽

Lingbo Kong

Keyword(s):

Molecular Mechanisms ◽

Inflammatory Diseases ◽

Therapeutic Strategies ◽

Research Progress ◽

Cellular Mechanisms ◽

Pharmacological Activities ◽

Current Review ◽

M2 Polarization ◽

Macrophages Polarization ◽

Herbal Plants

Macrophages M2 polarization have been taken as an anti-inflammatory progression during inflammation. Natural plant-derived products, with potential therapeutic and preventive activities against inflammatory diseases, have received increasing attention in recent years because of their whole regulative effects and specific pharmacological activities. However, the molecular mechanisms about how different kinds of natural compounds regulate macrophages polarization still unclear. Therefore, in the current review, we summarized the detailed research progress on the active compounds derived from herbal plants with regulating effects on macrophages, especially M2 polarization. These natural occurring compounds including flavonoids, terpenoids, glycosides, lignans, coumarins, alkaloids, polyphenols and quinones. In addition, we extensively discussed the cellular mechanisms underlying the M2 polarization for each compound, which could provide potential therapeutic strategies aiming macrophages M2 polarization.

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P.1.d.006 Aggravation of Toll-like receptor-4 (TLR4) mediated sickness behaviour by nucleotide-binding oligomerization domain-2 (NOD2) activation

European Neuropsychopharmacology ◽

10.1016/s0924-977x(12)70265-1 ◽

2012 ◽

Vol 22 ◽

pp. S185

Author(s):

A. Farzi ◽

E. Painsipp ◽

P. Holzer

Keyword(s):

Nucleotide Binding ◽

Toll Like Receptor ◽

Toll Like Receptor 4 ◽

Sickness Behaviour ◽

Oligomerization Domain

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Molecular Pathways Involved in the Development of Congenital Erythrocytosis

Genes ◽

10.3390/genes12081150 ◽

2021 ◽

Vol 12 (8) ◽

pp. 1150

Author(s):

Jana Tomc ◽

Nataša Debeljak

Keyword(s):

Signal Transduction ◽

Iron Homeostasis ◽

Molecular Mechanisms ◽

Oxygen Affinity ◽

Molecular Pathways ◽

Disease Development ◽

Post Translational Modifications ◽

Hemoglobin Oxygen Affinity ◽

Insight Into ◽

Idiopathic Erythrocytosis

Patients with idiopathic erythrocytosis are directed to targeted genetic testing including nine genes involved in oxygen sensing pathway in kidneys, erythropoietin signal transduction in pre-erythrocytes and hemoglobin-oxygen affinity regulation in mature erythrocytes. However, in more than 60% of cases the genetic cause remains undiagnosed, suggesting that other genes and mechanisms must be involved in the disease development. This review aims to explore additional molecular mechanisms in recognized erythrocytosis pathways and propose new pathways associated with this rare hematological disorder. For this purpose, a comprehensive review of the literature was performed and different in silico tools were used. We identified genes involved in several mechanisms and molecular pathways, including mRNA transcriptional regulation, post-translational modifications, membrane transport, regulation of signal transduction, glucose metabolism and iron homeostasis, which have the potential to influence the main erythrocytosis-associated pathways. We provide valuable theoretical information for deeper insight into possible mechanisms of disease development. This information can be also helpful to improve the current diagnostic solutions for patients with idiopathic erythrocytosis.

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Molecular Mechanisms of ZC3H12C/Reg-3 Biological Activity and Its Involvement in Psoriasis Pathology

International Journal of Molecular Sciences ◽

10.3390/ijms22147311 ◽

2021 ◽

Vol 22 (14) ◽

pp. 7311

Author(s):

Mateusz Wawro ◽

Jakub Kochan ◽

Weronika Sowinska ◽

Aleksandra Solecka ◽

Karolina Wawro ◽

...

Keyword(s):

Family Member ◽

Cellular Localization ◽

Molecular Mechanisms ◽

Inflammatory Diseases ◽

Association Studies ◽

Psoriasis Patient ◽

Genome Wide Association Studies ◽

Mrna Levels ◽

Transcript Levels

The members of the ZC3H12/MCPIP/Regnase family of RNases have emerged as important regulators of inflammation. In contrast to Regnase-1, -2 and -4, a thorough characterization of Regnase-3 (Reg-3) has not yet been explored. Here we demonstrate that Reg-3 differs from other family members in terms of NYN/PIN domain features, cellular localization pattern and substrate specificity. Together with Reg-1, the most comprehensively characterized family member, Reg-3 shared IL-6, IER-3 and Reg-1 mRNAs, but not IL-1β mRNA, as substrates. In addition, Reg-3 was found to be the only family member which regulates transcript levels of TNF, a cytokine implicated in chronic inflammatory diseases including psoriasis. Previous meta-analysis of genome-wide association studies revealed Reg-3 to be among new psoriasis susceptibility loci. Here we demonstrate that Reg-3 transcript levels are increased in psoriasis patient skin tissue and in an experimental model of psoriasis, supporting the immunomodulatory role of Reg-3 in psoriasis, possibly through degradation of mRNA for TNF and other factors such as Reg-1. On the other hand, Reg-1 was found to destabilize Reg-3 transcripts, suggesting reciprocal regulation between Reg-3 and Reg-1 in the skin. We found that either Reg-1 or Reg-3 were expressed in human keratinocytes in vitro. However, in contrast to robustly upregulated Reg-1 mRNA levels, Reg-3 expression was not affected in the epidermis of psoriasis patients. Taken together, these data suggest that epidermal levels of Reg-3 are negatively regulated by Reg-1 in psoriasis, and that Reg-1 and Reg-3 are both involved in psoriasis pathophysiology through controlling, at least in part different transcripts.

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Expression and function of Smad7 in autoimmune and inflammatory diseases

Journal of Molecular Medicine ◽

10.1007/s00109-021-02083-1 ◽

2021 ◽

Author(s):

Yiping Hu ◽

Juan He ◽

Lianhua He ◽

Bihua Xu ◽

Qingwen Wang

Keyword(s):

Posttranscriptional Regulation ◽

Molecular Mechanisms ◽

Transforming Growth Factor ◽

Inflammatory Diseases ◽

Kidney Diseases ◽

Critical Role ◽

Transforming Growth Factor Β ◽

Negative Regulator ◽

Signaling Mechanism ◽

And Function

AbstractTransforming growth factor-β (TGF-β) plays a critical role in the pathological processes of various diseases. However, the signaling mechanism of TGF-β in the pathological response remains largely unclear. In this review, we discuss advances in research of Smad7, a member of the I-Smads family and a negative regulator of TGF-β signaling, and mainly review the expression and its function in diseases. Smad7 inhibits the activation of the NF-κB and TGF-β signaling pathways and plays a pivotal role in the prevention and treatment of various diseases. Specifically, Smad7 can not only attenuate growth inhibition, fibrosis, apoptosis, inflammation, and inflammatory T cell differentiation, but also promotes epithelial cells migration or disease development. In this review, we aim to summarize the various biological functions of Smad7 in autoimmune diseases, inflammatory diseases, cancers, and kidney diseases, focusing on the molecular mechanisms of the transcriptional and posttranscriptional regulation of Smad7.

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