Raver1 links <i>Ripk1</i> RNA splicing to caspase-8-mediated pyroptotic cell death, inflammation, and pathogen resistance

B Boyao Zhang (Division of Infectious Diseases and Immunology, Department of Medicine, Program in Innate Immunity, University of Massachusetts Chan Medical School) P Pontus Orning (Division of Infectious Diseases and Immunology, Department of Medicine, Program in Innate Immunity, University of Massachusetts Chan Medical School) J Jesse W. Lehman (RNA Therapeutics Institute, University of Massachusetts Chan Medical School) A Alexandre Dinis (Division of Infectious Diseases and Immunology, Department of Medicine, Program in Innate Immunity, University of Massachusetts Chan Medical School) L Leslie Torres-Ulloa (RNA Therapeutics Institute, University of Massachusetts Chan Medical School) R Roland Elling (Institute for Immunodeficiency, Center of Chronic Immunodeficiency, University Medical Center, Faculty of Medicine, University of Freiburg) M Michelle A. Kelliher (Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Chan Medical School) J John Bertin (Immunology and Inflammation Therapeutic Area, Sanofi) M Megan K. Proulx (Department of Microbiology, University of Massachusetts Medical School) J Jon D. Goguen (Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School) L Liv Ryan (Department of Clinical and Molecular Medicine, Centre of Molecular Inflammation Research, Norwegian University of Science and Technology) R Richard K. Kandasamy (Division of Infectious Diseases and Immunology, Department of Medicine, Program in Innate Immunity, University of Massachusetts Chan Medical School) T Terje Espevik (Department of Clinical and Molecular Medicine, Centre of Molecular Inflammation Research, Norwegian University of Science and Technology) A Athma A. Pai (RNA Therapeutics Institute, University of Massachusetts Chan Medical School) K Katherine A. Fitzgerald (Department of Medicine, University of Massachusetts Chan Medical School) E Egil Lien (Division of Infectious Diseases and Immunology, Department of Medicine, Program in Innate Immunity, University of Massachusetts Chan Medical School)

Abstract

Multiple cell death and inflammatory signaling pathways converge on two critical factors: receptor-interacting serine/threonine kinase 1 (RIPK1) and caspase-8. Careful regulation of these molecules is critical to control apoptosis, pyroptosis, and inflammation. Here, we found a pivotal role of Raver1 as an essential regulator of Ripk1 pre-mRNA splicing, expression, and functionality and the subsequent caspase-8-dependent inflammatory cell death. We show that Raver1 influences mRNA diversity primarily by repressing alternative exon inclusion. Macrophages from Raver1 -deficient mice exhibit altered splicing of Ripk1 . As a result, Raver1 -deficient primary macrophages display diminished cell death and decreased interleukin-18 and interleukin-1ß production, when infected with Yersinia bacteria, or by restraining TGF-ß-activated kinase 1 or IKKβ in the presence of lipopolysaccharide, tumor necrosis factor family members, or interferon-γ. These responses are accompanied by reduced activation of caspase-8, Gasdermin D and E, and caspase-1 in the absence of Raver1 . Consequently, Raver1 -deficient mice showed heightened susceptibility to Yersinia infection. Raver1 and RIPK1 also controlled the expression and function of the C-type lectin receptor Mincle. Our study underscores the critical regulatory role of Raver1 in modulating innate immune responses and highlights its significance in directing in vivo and in vitro inflammatory processes.

Article Details

Volume / Issue Vol. 122, Issue 7
Published February 18, 2025
ISSN 0027-8424
Publisher National Academy of Sciences

Authors (16)

B

Boyao Zhang

Division of Infectious Diseases and Immunology, Department of Medicine, Program in Innate Immunity, University of Massachusetts Chan Medical School

P

Pontus Orning

Division of Infectious Diseases and Immunology, Department of Medicine, Program in Innate Immunity, University of Massachusetts Chan Medical School

J

Jesse W. Lehman

RNA Therapeutics Institute, University of Massachusetts Chan Medical School

A

Alexandre Dinis

Division of Infectious Diseases and Immunology, Department of Medicine, Program in Innate Immunity, University of Massachusetts Chan Medical School

L

Leslie Torres-Ulloa

RNA Therapeutics Institute, University of Massachusetts Chan Medical School

R

Roland Elling

Institute for Immunodeficiency, Center of Chronic Immunodeficiency, University Medical Center, Faculty of Medicine, University of Freiburg

M

Michelle A. Kelliher

Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Chan Medical School

J

John Bertin

Immunology and Inflammation Therapeutic Area, Sanofi

M

Megan K. Proulx

Department of Microbiology, University of Massachusetts Medical School

J

Jon D. Goguen

Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School

L

Liv Ryan

Department of Clinical and Molecular Medicine, Centre of Molecular Inflammation Research, Norwegian University of Science and Technology

R

Richard K. Kandasamy

Division of Infectious Diseases and Immunology, Department of Medicine, Program in Innate Immunity, University of Massachusetts Chan Medical School

T

Terje Espevik

Department of Clinical and Molecular Medicine, Centre of Molecular Inflammation Research, Norwegian University of Science and Technology

A

Athma A. Pai

RNA Therapeutics Institute, University of Massachusetts Chan Medical School

K

Katherine A. Fitzgerald

Department of Medicine, University of Massachusetts Chan Medical School

E

Egil Lien

Division of Infectious Diseases and Immunology, Department of Medicine, Program in Innate Immunity, University of Massachusetts Chan Medical School