title: Expression of DNA methyltransferases is influenced by growth hormone in the long-living Ames dwarf mouse in vivo and in vitro.
abstract: Methyltransferase expression and DNA methylation are linked to aging and age-related disease. We utilized 3-, 12-, and 24-month-old Ames dwarf and their wild-type siblings to examine the genotype and age-related differences in the expression of methyltransferase enzymes related to DNA methylation in the liver, glycine-N-methyltransferase and DNA methyltransferase (DNMT). We found that DNMT proteins and transcripts are differentially expressed in dwarf mice compared with wild-type siblings that can be attributed to age and/or genotype. However, DNMT1 protein expression is drastically reduced compared with wild-type controls at every age. DNMT3a protein levels coincide with differences observed in DNMT activity. Growth hormone appears to modulate expression of DNMT1 and 3a in dwarf liver tissue and primary hepatocytes. Therefore, growth hormone may contribute to age-related processes, DNA methylation, and, ultimately, longevity.
authors.affiliation: Department of Pharmacology, Physiology, and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks.
authors.forename: Vanessa L
authors.initials: VL
authors.lastname: Armstrong
authors.affiliation: Department of Pharmacology, Physiology, and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks.
authors.forename: Sharlene
authors.initials: S
authors.lastname: Rakoczy
authors.affiliation: Department of Pharmacology, Physiology, and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks.
authors.forename: Lalida
authors.initials: L
authors.lastname: Rojanathammanee
authors.affiliation: Department of Pharmacology, Physiology, and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks. holly.brown.borg@med.und.edu.
authors.forename: Holly M
authors.initials: HM
authors.lastname: Brown-Borg
mesh_terms: D000818:Animals; D003124:Colorimetry; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000378:metabolism; D019175:DNA Methylation / Q000502:physiology*; D000090205:DNA Methyltransferase 3A; D004393:Dwarfism, Pituitary / Q000378:metabolism; D050938:Glycine N-Methyltransferase / Q000378:metabolism; D013006:Growth Hormone / Q000378:metabolism / Q000502:physiology*; D022781:Hepatocytes / Q000378:metabolism; D015151:Immunoblotting; D008136:Longevity / Q000235:genetics / Q000502:physiology; D008780:Methyltransferases / Q000378:metabolism*; D051379:Mice; D008815:Mice, Inbred Strains; D012097:Repressor Proteins / Q000378:metabolism
chemical_list: C485852:Dmap1 protein, mouse; C000715535:Dnmt3a protein, mouse; D012097:Repressor Proteins; D013006:Growth Hormone; D008780:Methyltransferases; D050938:Glycine N-Methyltransferase; D004248:DNA (Cytosine-5-)-Methyltransferases; D000090205:DNA Methyltransferase 3A
keywords: Aging; Ames dwarf mice; DNA methylation; DNA methyltransferase; Glycine-N-methyltransferase; Liver.