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Ing1 functions in DNA demethylation by directing Gadd45a to H3K4me3.

ABSTRACT: Active DNA demethylation regulates epigenetic gene activation in numerous processes, but how the target site specificity of DNA demethylation is determined and what factors are involved are still poorly understood. Here we show that the tumor suppressor inhibitor of growth protein 1 (Ing1) is required for targeting active DNA demethylation. Ing1 functions by recruiting the regulator of DNA demethylation growth arrest and DNA damage protein 45a (Gadd45a) to histone H3 trimethylated at Lys 4 (H3K4me3). We show that reduced H3K4 methylation impairs recruitment of Gadd45a/Ing1 and gene-specific DNA demethylation. Our results indicate that histone methylation directs DNA demethylation.

SUBMITTER: Schafer A

PROVIDER: S-EPMC3576512 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

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Ing1 functions in DNA demethylation by directing Gadd45a to H3K4me3.

Schäfer Andrea A Karaulanov Emil E Stapf Ulrike U Döderlein Gabi G Niehrs Christof C

Genes & development 20130201 3

Active DNA demethylation regulates epigenetic gene activation in numerous processes, but how the target site specificity of DNA demethylation is determined and what factors are involved are still poorly understood. Here we show that the tumor suppressor inhibitor of growth protein 1 (Ing1) is required for targeting active DNA demethylation. Ing1 functions by recruiting the regulator of DNA demethylation growth arrest and DNA damage protein 45a (Gadd45a) to histone H3 trimethylated at Lys 4 (H3K4 ...[more]

PMID: 23388825

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