Oscillatory cAMP signaling rapidly alters H3K4 methylation

• Published in: Life science alliance 2020-01, Vol.3 (1), p.e201900529
• Main Authors: Huff, Tyler C, Camarena, Vladimir, Sant, David W, Wilkes, Zachary, Van Booven, Derek, Aron, Allegra T, Muir, Ryan K, Renslo, Adam R, Chang, Christopher J, Monje, Paula V, Wang, Gaofeng
• Format: Article
• Language: English
• Subjects: Animals; BASIC BIOLOGICAL SCIENCES; cell biology; Cells, Cultured; chromatin & epigenetics; Cyclic AMP - analogs & derivatives; Cyclic AMP - metabolism; Cyclic AMP - pharmacology; Demethylation - drug effects; Ferrous Compounds - metabolism; Gene Silencing; Histones - metabolism; Jumonji Domain-Containing Histone Demethylases - genetics; Jumonji Domain-Containing Histone Demethylases - metabolism; Ligands; Methylation - drug effects; Oxidoreductases, N-Demethylating - genetics; Oxidoreductases, N-Demethylating - metabolism; Protein Processing, Post-Translational - drug effects; Protein Processing, Post-Translational - genetics; Rats; Receptors, G-Protein-Coupled - metabolism; Schwann Cells; Signal Transduction - drug effects; Signal Transduction - genetics; Thionucleotides - metabolism; Thionucleotides - pharmacology; Transfection
• ISSN: 2575-1077; 2575-1077
• DOI: 10.26508/lsa.201900529

Epigenetic variation reflects the impact of a dynamic environment on chromatin. However, it remains elusive how environmental factors influence epigenetic events. Here, we show that G protein-coupled receptors (GPCRs) alter H3K4 methylation via oscillatory intracellular cAMP. Activation of Gs-coupled receptors caused a rapid decrease of H3K4me3 by elevating cAMP, whereas stimulation of Gi-coupled receptors increased H3K4me3 by diminishing cAMP. H3K4me3 gradually recovered towards baseline levels after the removal of GPCR ligands, indicating that H3K4me3 oscillates in tandem with GPCR activation. cAMP increased intracellular labile Fe(II), the cofactor for histone demethylases, through a non-canonical cAMP target-Rap guanine nucleotide exchange factor-2 (RapGEF2), which subsequently enhanced endosome acidification and Fe(II) release from the endosome via vacuolar H -ATPase assembly. Removing Fe(III) from the media blocked intracellular Fe(II) elevation after stimulation of Gs-coupled receptors. Iron chelators and inhibition of KDM5 demethylases abolished cAMP-mediated H3K4me3 demethylation. Taken together, these results suggest a novel function of cAMP signaling in modulating histone demethylation through labile Fe(II).