Geminivirus-encoded TrAP suppressor inhibits the histone methyltransferase SUVH4/KYP to counter host defense
- Texas A&M University, United States
- Jiangsu Academy of Agricultural Sciences, China
- Chinese Academy of Sciences, China
- Zhejiang University, China
Abstract
Transcriptional gene silencing (TGS) can serve as an innate immunity against invading DNA viruses throughout Eukaryotes. Geminivirus code for TrAP protein to suppress the TGS pathway. Here we identified an Arabidopsis H3K9me2 histone methyltransferase, Su(var)3-9 homolog 4 (SUVH4/KYP), as a bona fide cellular target of TrAP. TrAP interacts with the catalytic domain of KYP and inhibits its activity in vitro. TrAP elicits developmental anomalies phenocopying several TGS mutants, reduces the repressive H3K9me2 mark and CHH DNA methylation, and reactivates numerous endogenous KYP-repressed loci in vivo. Moreover, KYP binds to the viral chromatin, and controls its methylation to combat virus infection. Notably, kyp mutants support systemic infection of TrAP-deficient Geminivirus. We conclude that TrAP attenuates the TGS of the viral chromatin by inhibiting KYP activity to evade host surveillance. These findings provide new insight on the molecular arms race between host antiviral defense and virus counter defense at an epigenetic level.
Article and author information
Author details
Reviewing Editor
- Detlef Weigel, Max Planck Institute for Developmental Biology, Germany
Publication history
- Received: January 25, 2015
- Accepted: September 5, 2015
- Accepted Manuscript published: September 7, 2015 (version 1)
- Version of Record published: October 16, 2015 (version 2)
Copyright
© 2015, Castillo-González et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Geminivirus-encoded TrAP suppressor inhibits the histone methyltransferase SUVH4/KYP to counter host defense
eLife 4:e06671.
https://doi.org/10.7554/eLife.06671
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