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JMJ24 targets CHROMOMETHYLASE3 for proteasomal degradation in Arabidopsis.

ABSTRACT: H3K9 methylation is usually associated with DNA methylation, and together they symbolize transcriptionally silenced heterochromatin. A number of proteins involved in epigenetic processes have been characterized. However, how the stability of these proteins is regulated at the post-translational level is largely unknown. Here, we show that an Arabidopsis JmjC domain protein, JMJ24, possesses ubiquitin E3 ligase activity. JMJ24 directly targets a DNA methyltransferase, CHROMOMETHYLASE 3 (CMT3), for proteasomal degradation to initiate destabilization of the heterochromatic state of endogenous silenced loci. Our results uncover an additional connection between two conserved epigenetic modifications: histone modification and DNA methylation.

SUBMITTER: Deng S

PROVIDER: S-EPMC4743055 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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JMJ24 targets CHROMOMETHYLASE3 for proteasomal degradation in Arabidopsis.

Deng Shulin S Jang In-Cheol IC Su Linlin L Xu Jun J Chua Nam-Hai NH

Genes & development 20160121 3

H3K9 methylation is usually associated with DNA methylation, and together they symbolize transcriptionally silenced heterochromatin. A number of proteins involved in epigenetic processes have been characterized. However, how the stability of these proteins is regulated at the post-translational level is largely unknown. Here, we show that an Arabidopsis JmjC domain protein, JMJ24, possesses ubiquitin E3 ligase activity. JMJ24 directly targets a DNA methyltransferase, CHROMOMETHYLASE 3 (CMT3), fo ...[more]

PMID: 26798133

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Project description: Not available

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