Mutation of Arabidopsis SMC4 identifies condensin as a corepressor of pericentromeric transposons and conditionally expressed genes.
Genes Dev
; 31(15): 1601-1614, 2017 08 01.
Article
em En
| MEDLINE
| ID: mdl-28882854
ABSTRACT
In eukaryotes, transcriptionally inactive loci are enriched within highly condensed heterochromatin. In plants, as in mammals, the DNA of heterochromatin is densely methylated and wrapped by histones displaying a characteristic subset of post-translational modifications. Growing evidence indicates that these chromatin modifications are not sufficient for silencing. Instead, they are prerequisites for further assembly of higher-order chromatin structures that are refractory to transcription but not fully understood. We show that silencing of transposons in the pericentromeric heterochromatin of Arabidopsis thaliana requires SMC4, a core subunit of condensins I and II, acting in conjunction with CG methylation by MET1 (DNA METHYLTRANSFERASE 1), CHG methylation by CMT3 (CHROMOMETHYLASE 3), the chromatin remodeler DDM1 (DECREASE IN DNA METHYLATION 1), and histone modifications, including histone H3 Lys 27 monomethylation (H3K27me1), imparted by ATXR5 and ATXR6. SMC4/condensin also acts within the mostly euchromatic chromosome arms to suppress conditionally expressed genes involved in flowering or DNA repair, including the DNA glycosylase ROS1, which facilitates DNA demethylation. Collectively, our genome-wide analyses implicate condensin in the suppression of hundreds of loci, acting in both DNA methylation-dependent and methylation-independent pathways.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Elementos de DNA Transponíveis
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Arabidopsis
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Adenosina Trifosfatases
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Regulação da Expressão Gênica de Plantas
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Centrossomo
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Proteínas de Arabidopsis
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Complexos Multiproteicos
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Proteínas de Ligação a DNA
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Genes Dev
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Estados Unidos