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Nucleotide sequence-homology-independent breakdown of transgenic resistance by more virulent virus strains and a potential solution.

ABSTRACT: Controlling plant viruses by genetic engineering, including the globally important Papaya ringspot virus (PRSV), mainly involves coat protein (CP) gene mediated resistance via post-transcriptional gene silencing (PTGS). However, the breakdown of single- or double-virus resistance in CP-gene-transgenic papaya by more virulent PRSV strains has been noted in repeated field trials. Recombination analysis revealed that the gene silencing suppressor HC-Pro or CP of the virulent PRSV strain 5-19 is responsible for overcoming CP-transgenic resistance in a sequence-homology-independent manner. Transient expression assays using agro-infiltration in Nicotiana benthamiana plants indicated that 5-19 HC-Pro exhibits stronger PTGS suppression than the transgene donor strain. To disarm the suppressor from the virulent strain, transgenic papaya lines were generated carrying untranslatable 5-19 HC-Pro, which conferred complete resistance to 5-19 and other geographic PRSV strains. Our study suggested the potential risk of the emergence of more virulent virus strains, spurred by the deployment of CP-gene-transgenic crops, and provides a strategy to combat such strains.

SUBMITTER: Kung YJ

PROVIDER: S-EPMC5386206 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Nucleotide sequence-homology-independent breakdown of transgenic resistance by more virulent virus strains and a potential solution.

Kung Yi-Jung YJ You Bang-Jau BJ Raja Joseph A J JA Chen Kuan-Chun KC Huang Chiung-Huei CH Bau Huey-Jiunn HJ Yang Ching-Fu CF Huang Chung-Hao CH Chang Chung-Ping CP Yeh Shyi-Dong SD

Scientific reports 20150427

Controlling plant viruses by genetic engineering, including the globally important Papaya ringspot virus (PRSV), mainly involves coat protein (CP) gene mediated resistance via post-transcriptional gene silencing (PTGS). However, the breakdown of single- or double-virus resistance in CP-gene-transgenic papaya by more virulent PRSV strains has been noted in repeated field trials. Recombination analysis revealed that the gene silencing suppressor HC-Pro or CP of the virulent PRSV strain 5-19 is res ...[more]

PMID: 25913508

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Nucleotide sequence-homology-independent breakdown of transgenic resistance by more virulent virus strains and a potential solution.

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Nucleotide sequence-homology-independent breakdown of transgenic resistance by more virulent virus strains and a potential solution.

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