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Dicer is required for chromosome segregation and gene silencing in fission yeast cells.

ABSTRACT: RNA interference is a form of gene silencing in which the nuclease Dicer cleaves double-stranded RNA into small interfering RNAs. Here we report a role for Dicer in chromosome segregation of fission yeast. Deletion of the Dicer (dcr1+) gene caused slow growth, sensitivity to thiabendazole, lagging chromosomes during anaphase, and abrogated silencing of centromeric repeats. As Dicer in other species, Dcr1p degraded double-stranded RNA into approximately 23 nucleotide fragments in vitro, and dcr1Delta cells were partially rescued by expression of human Dicer, indicating evolutionarily conserved functions. Expression profiling demonstrated that dcr1+ was required for silencing of two genes containing a conserved motif.

SUBMITTER: Provost P

PROVIDER: S-EPMC139198 | biostudies-literature | 2002 Dec

REPOSITORIES: biostudies-literature

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Dicer is required for chromosome segregation and gene silencing in fission yeast cells.

Provost Patrick P Silverstein Rebecca A RA Dishart David D Walfridsson Julian J Djupedal Ingela I Kniola Barbara B Wright Anthony A Samuelsson Bengt B Radmark Olof O Ekwall Karl K

Proceedings of the National Academy of Sciences of the United States of America 20021213 26

RNA interference is a form of gene silencing in which the nuclease Dicer cleaves double-stranded RNA into small interfering RNAs. Here we report a role for Dicer in chromosome segregation of fission yeast. Deletion of the Dicer (dcr1+) gene caused slow growth, sensitivity to thiabendazole, lagging chromosomes during anaphase, and abrogated silencing of centromeric repeats. As Dicer in other species, Dcr1p degraded double-stranded RNA into approximately 23 nucleotide fragments in vitro, and dcr1D ...[more]

PMID: 12482946

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