Cryo-EM Structures of MDA5-dsRNA Filaments at Different Stages of ATP Hydrolysis

Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved..

Double-stranded RNA (dsRNA) is a potent proinflammatory signature of viral infection. Long cytosolic dsRNA is recognized by MDA5. The cooperative assembly of MDA5 into helical filaments on dsRNA nucleates the assembly of a multiprotein type I interferon signaling platform. Here, we determined cryoelectron microscopy (cryo-EM) structures of MDA5-dsRNA filaments with different helical twists and bound nucleotide analogs at resolutions sufficient to build and refine atomic models. The structures identify the filament-forming interfaces, which encode the dsRNA binding cooperativity and length specificity of MDA5. The predominantly hydrophobic interface contacts confer flexibility, reflected in the variable helical twist within filaments. Mutation of filament-forming residues can result in loss or gain of signaling activity. Each MDA5 molecule spans 14 or 15 RNA base pairs, depending on the twist. Variations in twist also correlate with variations in the occupancy and type of nucleotide in the active site, providing insights on how ATP hydrolysis contributes to MDA5-dsRNA recognition.

Medienart:

E-Artikel

Erscheinungsjahr:

2018

Erschienen:

2018

Enthalten in:

Zur Gesamtaufnahme - volume:72

Enthalten in:

Molecular cell - 72(2018), 6 vom: 20. Dez., Seite 999-1012.e6

Sprache:

Englisch

Beteiligte Personen:

Yu, Qin [VerfasserIn]
Qu, Kun [VerfasserIn]
Modis, Yorgo [VerfasserIn]

Links:

Volltext

Themen:

77238-31-4
8L70Q75FXE
AGS
ATPase
Adenosine Triphosphate
Aicardi-Goutières syndrome
Cryo-EM
Cryoelectron microscopy
DExD/H-box RNA helicase
EC 3.6.1.-
EC 3.6.4.13
Helical reconstruction
IFIH1 protein, human
Ifih1 protein, mouse
Innate immune pattern recognition
Interferon-Induced Helicase, IFIH1
Interferon-beta
Journal Article
Nucleic acid sensing
RIG-I-like receptor
RLR
RNA, Double-Stranded
Research Support, Non-U.S. Gov't
SF2 helicases
SMS
Singleton-Merten syndrome
Superfamily 2 helicases
Video-Audio Media

Anmerkungen:

Date Completed 28.05.2019

Date Revised 29.01.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.molcel.2018.10.012

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM290818109