Dataset Information

The inflammasome-activated cytokine IL-1 is targeted for ubiquitylation and proteasomal degradation to limit its inflammatory potential

ABSTRACT: Interleukin-1B (IL-1B) is pathologically activated by inflammasome-associated caspase-1 in rare autoinflammatory conditions and in wide-spread diseases. Therefore, IL-1B activity must be fine-tuned to enable anti-microbial responses whilst limiting collateral damage. Here we report that, relative to other inflammasome components, IL-1B is rapidly turned over by the proteasome and this correlates with its decoration by K11-, K63- and K48-linked ubiquitin chains. This IL-1 degradation signal is not only a feature of inflammasome priming but is also triggered upon inflammasome activation. We demonstrate that IL-1 K133 is modified by ubiquitin and forms a salt bridge with IL-1B D129. Loss of IL-1 K133 ubiquitylation, or disruption of the K133:D129 electrostatic interaction, stabilizes IL-1Bprotein levels. Accordingly, IL-1B K133R/K133R mice display increased precursor IL-1Bupon inflammasome priming and increased bioactive IL-1B following inflammasome activation, both in vitro and following LPS injection in vivo. These findings reveal new mechanisms for limiting IL-1B activity and safeguarding against damaging inflammation.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Permanent Cell Line Cell

SUBMITTER: Laura Dagley

LAB HEAD: James Vince

PROVIDER: PXD021305 | Pride | 2021-04-01

REPOSITORIES: Pride

ACCESS DATA

Publications

The ubiquitylation of IL-1β limits its cleavage by caspase-1 and targets it for proteasomal degradation.

Vijayaraj Swarna L SL Feltham Rebecca R Rashidi Maryam M Frank Daniel D Liu Zhengyang Z Simpson Daniel S DS Ebert Gregor G Vince Angelina A Herold Marco J MJ Kueh Andrew A Pearson Jaclyn S JS Dagley Laura F LF Murphy James M JM Webb Andrew I AI Lawlor Kate E KE Vince James E JE

Nature communications 20210511 1

Interleukin-1β (IL-1β) is activated by inflammasome-associated caspase-1 in rare autoinflammatory conditions and in a variety of other inflammatory diseases. Therefore, IL-1β activity must be fine-tuned to enable anti-microbial responses whilst limiting collateral damage. Here, we show that precursor IL-1β is rapidly turned over by the proteasome and this correlates with its decoration by K11-linked, K63-linked and K48-linked ubiquitin chains. The ubiquitylation of IL-1β is not just a degradatio ...[more]

PMID: 33976225

Similar Datasets

Project description:IL-1B is an important cytokine that is often found to be up-regulated during osteoarthritic and rheumatoid joint diseases. It is viewed as a catabolic factor, inducing enzymes that allow for the degradation of the cartilage extracellular matrix and also has essential roles as an autocrine and paracrine factor in fibronectin fragment-mediated degradation. It can also reduce the synthesis of the major cartilage components, type II collagen and aggrecan. On the other hand, IL-1B also has the ability to induce the growth and morphogenic factor BMP-2. During joint diseases, IL-1B is synthesized by both synovial cells and chondrocytes. Addition of IL-1 biological antagonists such as IL-1 receptor antagonists can suppress cartilage degradation in vitro. Thus, the production of IL-1B could act as the first step in mediating a cascade of other mediators in cartilage which could be relevant to the fate of the cartilage. In order to obtain a global picture of the effect of IL-1B production on human adult articular chondrocytes, we analyzed changes in gene expression induced by IL-1B by microarray analysis. We found that IL-1B has a diverse effect on gene expression profile in chondrocytes. One of the predominant responses that we observed in adult human articular chondrocytes on exposure to IL-1B is a dramatic increase in a large set of chemokines and other genes related to the inflammatory cascade. Keywords: Gene response to IL-1B (10 ng/ml) Cartilage was obtained from adult human tissue donors with above the knee amputations due to chondrosarcoma or traumatic injury or from autopsy. Chondrocytes were isolated following established protocols, maintained in high density, and treated with IL-1B (10 ng/ml). Chondrocytes treated with buffer only served as the untreated control. The experiment was carried out in duplicate. Total RNA was extracted from these chondrocytes, labeled with fluorophores (Cy3 or Cy5) and analyzed for expression changes using the Human Operon/Qiagen v3.0 oligonucleotide array. The analysis was repeated with the fluorophore dyes exchanged between the untreated and experimental RNAs.

Project description:BACKGROUND: Cryopyrin-Associated Periodic Syndrome (CAPS) is an autoinflammatory condition consequence of monoallelic variants in the NLRP3 gene that exacerbate IL-1β production. These variants are gain-of-function, but the exact regulatory mechanism of the NLRP3 CAPS-inflammasome is not well yet understood. It is considered as a hypersensitive inflammasome triggered by cell priming, but patients with CAPS and animal disease models present inflammatory flares in the absence of external triggers.OBJECTIVES: To study the regulation and activation of the NLRP3 inflammasome in CAPS.METHODS: CAPS derived blood samples and genetically modified macrophages expressing different NLRP3 CAPS-associated variants were used to assess NLRP3 function dissociated from cell priming and cell metabolism.RESULTS: We found that CAPS-associated variants constitutively result in active NLRP3 inflammasomes, that induce a basal cleavage of gasdermin D, IL-18 release and pyroptosis. The constitutive active NLRP3 inflammasome was blocked by MCC950 and was dependent on NLRP3 expression level, being further regulated by deubiquitination. We also showed that activation of NF-κB with lipopolysaccharide or other endogenous host-derived molecules (palmitate, S100A9 or IL-6) further modulated the activation of the NLRP3 CAPS inflammasome and expanded the repertoire of molecules secreted from CAPS macrophages to IL-1β, IL-1α, HMGB1, cystatin B and the P2X7 receptor, identifying novel proteins involved in CAPS pathogenesis. NLRP3 inflammasomes with CAPS associated variants affected the immunometabolism of the myeloid compartment and impaired glycolysis.CONCLUSIONS: These findings demonstrate that NLRP3 CAPS-associated variants form a constitutive active inflammasome that induce basal pyroptosis and IL-18 release without cell priming, suggesting a priming-independent mechanism for the initiation of CAPS flares characterized with a profound affection in the immunometabolism.

Dataset Information

The inflammasome-activated cytokine IL-1 is targeted for ubiquitylation and proteasomal degradation to limit its inflammatory potential

Publications

The ubiquitylation of IL-1β limits its cleavage by caspase-1 and targets it for proteasomal degradation.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure