Logo image
Effects of allelic variations in the human myxovirus resistance protein A on its antiviral activity
Journal article   Open access   Peer reviewed

Effects of allelic variations in the human myxovirus resistance protein A on its antiviral activity

Laura Graf, Alexej Dick, Franziska Sendker, Emanuel Barth, Manja Marz, Oliver Daumke and Georg Kochs
The Journal of biological chemistry, v 293(9), pp 3056-3072
02 Mar 2018
PMID: 29330299
url
https://doi.org/10.1074/jbc.M117.812784View
Published, Version of Record (VoR) Open

Abstract

allelic variations antiviral response dynamin genetic polymorphism influenza virus innate immunity interferon Mx proteins
Only a minority of patients infected with seasonal influenza A viruses exhibit a severe or fatal outcome of infection, but the reasons for this inter-individual variability in influenza susceptibility are unclear. To gain further insights into the molecular mechanisms underlying this variability, we investigated naturally occurring allelic variations of the myxovirus resistance 1 (MX1) gene coding for the influenza restriction factor MxA. The interferon-induced dynamin-like GTPase consists of an N-terminal GTPase domain, a bundle signaling element, and a C-terminal stalk responsible for oligomerization and viral target recognition. We used online databases to search for variations in the MX1 gene. Deploying in vitro approaches, we found that non-synonymous variations in the GTPase domain cause the loss of antiviral and enzymatic activities. Furthermore, we showed that these amino acid substitutions disrupt the interface for GTPase domain dimerization required for the stimulation of GTP hydrolysis. Variations in the stalk were neutral or slightly enhanced or abolished MxA antiviral function. Remarkably, two other stalk variants altered MxA's antiviral specificity. Variations causing the loss of antiviral activity were found only in heterozygous carriers. Interestingly, the inactive stalk variants blocked the antiviral activity of WT MxA in a dominant-negative way, suggesting that heterozygotes are phenotypically MxA-negative. In contrast, the GTPase-deficient variants showed no dominant-negative effect, indicating that heterozygous carriers should remain unaffected. Our results demonstrate that naturally occurring mutations in the human MX1 gene can influence MxA function, which may explain individual variations in influenza virus susceptibility in the human population.

Metrics

9 Record Views
19 citations in Scopus

Details

UN Sustainable Development Goals (SDGs)

This publication has contributed to the advancement of the following goals:

#3 Good Health and Well-Being

InCites Highlights

Data related to this publication, from InCites Benchmarking & Analytics tool:

Collaboration types
Domestic collaboration
Web of Science research areas
Biochemistry & Molecular Biology
Logo image