PICKLE-mediated nucleosome condensing drives H3K27me3 spreading for the inheritance of Polycomb memory during differentiation.
Mol Cell
; 84(18): 3438-3454.e8, 2024 Sep 19.
Article
em En
| MEDLINE
| ID: mdl-39232583
ABSTRACT
Spreading of H3K27me3 is crucial for the maintenance of mitotically inheritable Polycomb-mediated chromatin silencing in animals and plants. However, how Polycomb repressive complex 2 (PRC2) accesses unmodified nucleosomes in spreading regions for spreading H3K27me3 remains unclear. Here, we show in Arabidopsis thaliana that the chromatin remodeler PICKLE (PKL) plays a specialized role in H3K27me3 spreading to safeguard cell identity during differentiation. PKL specifically localizes to H3K27me3 spreading regions but not to nucleation sites and physically associates with PRC2. Loss of PKL disrupts the occupancy of the PRC2 catalytic subunit CLF in spreading regions and leads to aberrant dedifferentiation. Nucleosome density increase endowed by the ATPase function of PKL ensures that unmodified nucleosomes are accessible to PRC2 catalytic activity for H3K27me3 spreading. Our findings demonstrate that PKL-dependent nucleosome compaction is critical for PRC2-mediated H3K27me3 read-and-write function in H3K27me3 spreading, thus revealing a mechanism by which repressive chromatin domains are established and propagated.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Histonas
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Nucleossomos
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Diferenciação Celular
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Arabidopsis
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Proteínas de Arabidopsis
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Montagem e Desmontagem da Cromatina
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Complexo Repressor Polycomb 2
Idioma:
En
Revista:
Mol Cell
/
Mol. cell
/
Molecular cell
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
China