Journal Article

Herpesviruses induce aggregation and selective autophagy of host signalling proteins NEMO and RIPK1 as an immune-evasion mechanism

Schmitz, Rebekka, Krause, Eva, Reimer, Rudolph, Muscolino, Elena, Schneider, Carola, Ostermann, Eleonore, Caragliano, Enrico, Sickmann, Albert, Kim, Young-Hyun, Brune, Wolfram, Rizzato, Matteo, Loroch, Stefan, Juranić Lisnić, Vanda

2020

Overview

Viruses manipulate cellular signalling by inducing the degradation of crucial signal transducers, usually via the ubiquitin–proteasome pathway. Here, we show that the murine cytomegalovirus (Murid herpesvirus 1) M45 protein induces the degradation of two cellular signalling proteins, the nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) essential modulator (NEMO) and the receptor-interacting protein kinase 1 (RIPK1), via a different mechanism: it induces their sequestration as insoluble protein aggregates and subsequently facilitates their degradation by autophagy. Aggregation of target proteins requires a distinct sequence motif in M45, which we termed ‘induced protein aggregation motif’. In a second step, M45 recruits the retromer component vacuolar protein sorting 26B (VPS26B) and the microtubule-associated protein light chain 3 (LC3)-interacting adaptor protein TBC1D5 to facilitate degradation of aggregates by selective autophagy. The induced protein aggregation motif is conserved in M45-homologous proteins of several human herpesviruses, including herpes simplex virus, Epstein–Barr virus and Kaposi’s sarcoma-associated herpesvirus, but is only partially conserved in the human cytomegalovirus UL45 protein. We further show that the HSV-1 ICP6 protein induces RIPK1 aggregation and degradation in a similar fashion to M45. These data suggest that induced protein aggregation combined with selective autophagy of aggregates (aggrephagy) represents a conserved viral immune-evasion mechanism. Herpesviruses are shown to specifically block innate antiviral responses by inducing the aggregation of key signalling molecules nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) essential modulator (NEMO) and receptor-interacting protein kinase 1 (RIPK1) and their degradation by selective autophagy, thereby blocking the activation of NF-κB and the induction of necroptosis, respectively.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: 14/19 / 14/28 / 42/70 / 45/44 / 631/326/596 / 631/326/596/1553 / 631/80/39 / 631/80/82 / 631/80/86 / 64/60 / 82/51 / 82/58 / 82/80 / 96/95 / Animals / Autophagy / Autophagy - immunology / Autophagy-Related Protein 5 - deficiency / Autophagy-Related Protein 5 - genetics / Biomedical and Life Sciences / Cells, Cultured / Cytomegalovirus / Degradation / Epstein-Barr virus / HEK293 Cells / Herpes simplex / Herpesviridae - immunology / Herpesviridae - metabolism / Herpesviridae - pathogenicity / Herpesvirus 1, Human - immunology / Herpesvirus 1, Human - metabolism / Herpesvirus 1, Human - pathogenicity / Host Microbial Interactions - immunology / Humans / Immune Evasion / Infectious Diseases / Intracellular Signaling Peptides and Proteins - chemistry / Intracellular Signaling Peptides and Proteins - immunology / Intracellular Signaling Peptides and Proteins - metabolism / Kaposi's sarcoma / Kinases / Life Sciences / Lymphocytes B / Medical Microbiology / Mice / Mice, Inbred C57BL / Microbiology / Models, Biological / Muromegalovirus - immunology / Muromegalovirus - metabolism / Muromegalovirus - pathogenicity / Necroptosis / NF-κB protein / Parasitology / Phagocytosis / Proteasomes / Protein Aggregates - immunology / Protein interaction / Protein kinase / Protein transport / Proteins / Proteolysis / Receptor-Interacting Protein Serine-Threonine Kinases - chemistry / Receptor-Interacting Protein Serine-Threonine Kinases - immunology / Receptor-Interacting Protein Serine-Threonine Kinases - metabolism / Ribonucleotide Reductases - genetics / Ribonucleotide Reductases - immunology / Ribonucleotide Reductases - metabolism / Sarcoma / Signal transduction / Ubiquitin / Viral Proteins - genetics / Viral Proteins - immunology / Viral Proteins - metabolism / Virology