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A mouse polyomavirus-encoded microRNA targets the cellular apoptosis pathway through Smad2 inhibition.

ABSTRACT: Some viruses and most eukaryotic cells have microRNAs that regulate the expression of many genes. Although many viral miRNAs have been identified, only a few have been included in in vivo functional studies. Here we show that a Py-encoded miRNA downregulates the expression of the pro-apoptotic factor Smad2, resulting in the suppression of the apoptosis pathway. To study the Py miRNA in an in vivo context, a miRNA-deficient mutant virus was created on the background of the LID virus strain which establishes a rapid and lethal infection in newborn mice. Apoptosis analysis on kidney tissues indicates that the pro-apoptotic pathway is targeted in the infected host as well. Suppression of apoptosis through targeting of Smad2 by the Py miRNA is expected to synergize with anti-apoptotic effects previously attributed to the polyoma tumor antigens in support of virus replication in the natural host.

SUBMITTER: Sung CK

PROVIDER: S-EPMC4253860 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature

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A mouse polyomavirus-encoded microRNA targets the cellular apoptosis pathway through Smad2 inhibition.

Sung Chang Kyoo CK Yim Hyungshin H Andrews Erik E Benjamin Thomas L TL

Virology 20140820

Some viruses and most eukaryotic cells have microRNAs that regulate the expression of many genes. Although many viral miRNAs have been identified, only a few have been included in in vivo functional studies. Here we show that a Py-encoded miRNA downregulates the expression of the pro-apoptotic factor Smad2, resulting in the suppression of the apoptosis pathway. To study the Py miRNA in an in vivo context, a miRNA-deficient mutant virus was created on the background of the LID virus strain which ...[more]

PMID: 25146733

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