Changes in nucleosome occupancy associated with metabolic alterations in aged mammalian liver
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
SUBMITTER: Irina Bochkis
PROVIDER: E-GEOD-58006 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
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Project description:Aging is accompanied by physiological impairments, which, in insulin-responsive tissues, including the liver, predispose individuals to metabolic disease. However, the molecular mechanisms underlying these changes remain largely unknown. Here, we analyze genome-wide profiles of RNA and chromatin organization in the liver of young (3 months) and old (21 months) mice. Transcriptional changes suggest that de-repression of the nuclear receptors PPARM-NM-1, PPARM-NM-3, and LXRM-NM-1 in aged mouse liver leads to activation of targets regulating lipid synthesis and storage, whereas age-dependent changes in nucleosome occupancy are associated with binding sites for both known regulators (forkhead factors and nuclear receptors) and for novel candidates associated with nuclear lamina (Hdac3 and Srf) implicated to govern metabolic function of aging liver. Winged-helix factor Foxa2 and nuclear receptor co-repressor Hdac3 exhibit reciprocal binding pattern at PPARM-NM-1 targets contributing to gene expression changes that lead to steatosis in aged liver. Genome-wide nucleosome profiles (MNase-Seq) from young (3 months) and old (21 months) mouse livers
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Project description:Aging is accompanied by physiological impairments, which, in insulin-responsive tissues, including the liver, predispose individuals to metabolic disease. However, the molecular mechanisms underlying these changes remain largely unknown. Here, we analyze genome-wide profiles of RNA and chromatin organization in the liver of young (3 months) and old (21 months) mice. Transcriptional changes suggest that de-repression of the nuclear receptors PPARα, PPARγ, and LXRα in aged mouse liver leads to activation of targets regulating lipid synthesis and storage, whereas age-dependent changes in nucleosome occupancy are associated with binding sites for both known regulators (forkhead factors and nuclear receptors) and for novel candidates associated with nuclear lamina (Hdac3 and Srf) implicated to govern metabolic function of aging liver. Winged-helix factor Foxa2 and nuclear receptor co-repressor Hdac3 exhibit reciprocal binding pattern at PPARα targets contributing to gene expression changes that lead to steatosis in aged liver. Genome-wide location analysis (ChIP-Seq) of Foxa2 and Hdac3 from young (3 months) and old (21 months) mouse livers
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