Outer membrane protein 25 of Brucella suppresses TLR-mediated expression of proinflammatory cytokines through degradation of TLRs and adaptor proteins

Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved..

Toll-like receptors (TLRs) are essential components of innate immunity that serves as the first line of defense against the invaded microorganisms. However, successful infectious pathogens subvert TLR signaling to suppress the activation of innate and adaptive responses. Brucella species are infectious intracellular bacterial pathogens causing the worldwide zoonotic disease, brucellosis, that impacts economic growth of many countries. Brucella species are considered as stealthy bacterial pathogens as they efficiently evade or suppress host innate and adaptive immune responses for their chronic persistence. However, the bacterial effectors and their host targets for modulating the immune responses remain obscure. Brucella encodes various outer membrane proteins (Omps) that facilitate their invasion, intracellular replication, and immunomodulation. Outer membrane protein 25 (Omp25) of Brucella plays an important role in the immune modulation through suppression of proinflammatory cytokines. However, the mechanism and the signaling pathways that are targeted by Omp25 to attenuate the production of proinflammatory cytokines remain obscure. Here, we report that Omp25 and its variants, viz. Omp25b, Omp25c, and Omp25d, suppress production of proinflammatory cytokines that are mediated by various TLRs. Furthermore, we demonstrate that Omp25 and its variants promote enhanced ubiquitination and degradation of TLRs and their adaptor proteins to attenuate the expression of proinflammatory cytokines. Targeting multiple TLRs and adaptor proteins enables Omp25 to effectively suppress the expression of proinflammatory cytokines that are induced by diverse pathogen-associated molecular patterns. This can contribute to the defective adaptive immune response and the chronic persistence of Brucella in the host.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:299

Enthalten in:

The Journal of biological chemistry - 299(2023), 11 vom: 30. Nov., Seite 105309

Sprache:

Englisch

Beteiligte Personen:

Murugan, Subathra [VerfasserIn]
Nandi, Binita Roy [VerfasserIn]
Mazumdar, Varadendra [VerfasserIn]
Joshi, Kiranmai [VerfasserIn]
Nandini, Prachita [VerfasserIn]
Namani, Swapna [VerfasserIn]
Jakka, Padmaja [VerfasserIn]
Radhakrishnan, Girish K [VerfasserIn]

Links:

Volltext

Themen:

Adaptor Proteins, Signal Transducing
Bacterial Outer Membrane Proteins
Brucella
Cytokines
Innate immunity
Journal Article
Outer membrane proteins
Proinflammatory cytokines
Research Support, Non-U.S. Gov't
Toll-Like Receptors
Toll-like receptors
Ubiquitination

Anmerkungen:

Date Completed 29.11.2023

Date Revised 06.02.2024

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.jbc.2023.105309

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM362746079