Estrogen receptor beta regulates locus-specific DNA methylation a possible mechanism for epigenetic effects of endocrine disrupters

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1 Estrogen receptor beta regulates locus-specific DNA methylation a possible mechanism for epigenetic effects of endocrine disrupters Joëlle Rüegg Swedish Toxicology Science Research Center, Swetox Karolinska Institutet

2 EDCs and human health Bisphenol A Epigenetic mechanisms Behavioural and psychiatric disorders Phthalates DNA methylation Cancer Methoxychlor Histone code Impaired sexual development Decreased fertility Dioxins The study of heritable changes in gene function that cannot be explained by changes in the genetic sequence Obesity and diabetes II

3 Regulation of DNA methylation 5mC C + BER 5caC 5fC 5hmC But how are these factors targeted? February 15, 16 Reik and Walter, Nature Reviews, 1

4 EDC targets bind to specific genomic loci Nucleus ER ER ERE Estrogen receptor alpha & beta Androgen receptor Glucocortiocoid receptor Thyroid hormone receptor Retinoic acid receptors Arylhydrocarbon receptor Can ERs (and other nuclear receptors) regulate DNA methylation? Is this a mechanism underlying epigenetic effects of EDCs?

5 % methylation relative enrichment relative relative enrichment 5 1 ERb is involved in 5 regulation of DNA methylation CpG CpG HoxA 9 HoxA 9 CpG CpG wt wt berko berkoherb berkoherb 1 1 HKm HoxA9 HoxA9 HKm wt wt berko berko berkoherb berkoherb HKm HKm 55 hypermethylated loci 16 hypomethylated loci HK7m HK7m HoxA9 HoxA9 K7m HK7m HK9m HK9m HK9m HK9m wt wt berko berkoherb berkoherb wt wt berko berko berkoherb berkoherb Liu et al., in revision

6 6 ERbeta interacts with relative enrichment 5mC Far western blot analysis C 5hmC + BER 5caC 5fC ChIP in MEFs wt berko berkoherb Liu et al., in revision ERb interacts with and recruits it to regions that are differentially methylated in the absence of ERb HoxA1 Tnfaip Pitx1

7 7 Working model ESC Differentiation Neuron TET EDCs ER DNMT ER C 5mC 5hmC 5fC 5caC HT mouse hippocampal cells Change to medium w/o BPA Fkbp5 Harvest days days Differentiation +/- BPA

8 Fkbp51/actin ratio relative expression relative expression relative expression D 8 ERbeta mediates effects of BPA on DNA methylation CpG 5 DNA methylation at Fkbp5 CpG 6 Fkbp5 methylation # no BPA 1 nm BPA B C B C Fkbp5 expression sh 1 nm BPA ERb expression 1 nm BPA 1 nm BPA sherbeta Fkbp5 expression ### # sh sherb.5. sh sherb Kitraki et al., MCE 15 shc

9 9 Summary ESC Differentiation Neuron TET EDCs ER DNMT ER C 5mC 5hmC 5fC 5caC ERb ko leads to differentially methylated loci ERb interacts with is ERb-dependently recruited to genes whose methylation is regulated by ERb BPA exposure during differentiation/development affects methylation of Fkbp5 ERb is involved in mediating BPA s effect on Fkbp5 methylation

10 1 Thanks to All my colleagues at My collaborators and former colleagues Group Ekström National and Kapodistrian University of Athens: Efthymia Kitraki Group Schär Genomatix GmbH: Nancy Bretschneider Martin Seifert you for your attention! Fonds zur Förderung des akademischen Nachwuchses

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12 relative expression Fkbp51/ Gapdh ratio Fkbp51/ Gapdh ratio Fkbp51/actin Fkbp nm BPA 1 nm BPA 1 nm BPA..5 Connecting Figure in vitro and in vivo results Figure 1 (small basal column size) a. BPA a. In utero exposure to BPA BPA HT cells undifferentiated Change differentiated to medium BPA w/o BPA/ICI Harvest B d BPA d days days h rfkbp5 intron 5 1 Differentiation +/- BPA, +/- ICI rfkbp5 intron 5 Dex treatment mfkbp5 intron 5 rfkbp5 intron 5 69 bp mfkbp5 intron 5 mfkbp5 intron 5 68 bp Fkbp5 expression e e CpG 5 Liu et al., Life Sciences, DNA methylation at Fkbp5 CpG 5 CpG 6 b no BPA nm BPA 1. CpG CpG1 CpG basal CpG b no BPA 1 nm BPA CpG CpG CpG6 CpG1. post stress CpG basal CpG CpG Fkbp51 expression CpG7 C BPA Kitraki et al., MCE 15 CpG5 1 CpG6 post stress CpG1 CpG7 DNA methylation male at Fkbp5 CpG CpG BPA CpG CpG5 post stress Panagiotidou et al., J. Endo 1 CpG6 CpG7