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Soybean antiviral immunity conferred by dsRNase targets the viral replication complex.

ABSTRACT: Eukaryotic positive-strand RNA viruses replicate their genomes in membranous compartments formed in a host cell, which sequesters the dsRNA replication intermediate from antiviral immune surveillance. Here, we find that soybean has developed a way to overcome this sequestration. We report the positional cloning of the broad-spectrum soybean mosaic virus resistance gene Rsv4, which encodes an RNase H family protein with dsRNA-degrading activity. An active-site mutant of Rsv4 is incapable of inhibiting virus multiplication and is associated with an active viral RNA polymerase complex in infected cells. These results suggest that Rsv4 enters the viral replication compartment and degrades viral dsRNA. Inspired by this model, we design three plant-gene-derived dsRNases that can inhibit the multiplication of the respective target viruses. These findings suggest a method for developing crops resistant to any target positive-strand RNA virus by fusion of endogenous host genes.

SUBMITTER: Ishibashi K

PROVIDER: S-EPMC6764979 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Soybean antiviral immunity conferred by dsRNase targets the viral replication complex.

Ishibashi Kazuhiro K Saruta Masayasu M Shimizu Takehiko T Shu Miao M Anai Toyoaki T Komatsu Kunihiko K Yamada Naohiro N Katayose Yuichi Y Ishikawa Masayuki M Ishimoto Masao M Kaga Akito A

Nature communications 20190927 1

Eukaryotic positive-strand RNA viruses replicate their genomes in membranous compartments formed in a host cell, which sequesters the dsRNA replication intermediate from antiviral immune surveillance. Here, we find that soybean has developed a way to overcome this sequestration. We report the positional cloning of the broad-spectrum soybean mosaic virus resistance gene Rsv4, which encodes an RNase H family protein with dsRNA-degrading activity. An active-site mutant of Rsv4 is incapable of inhib ...[more]

PMID: 31562302

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Soybean antiviral immunity conferred by dsRNase targets the viral replication complex.

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Soybean antiviral immunity conferred by dsRNase targets the viral replication complex.

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