title: Glutamine contributes to maintenance of mouse embryonic stem cell self-renewal through PKC-dependent downregulation of HDAC1 and DNMT1/3a.
abstract: Although glutamine (Gln) is not an essential amino acid, it is considered a critical substrate in many key metabolic processes that control a variety of physiological functions and are involved in regulating early embryonic development. Thus, we investigated the effect of Gln on regulation of mouse embryonic stem cell (mESC) self-renewal and related signaling pathways. Gln deprivation decreased Oct4 expression as well as expression of cell cycle regulatory proteins. However, Gln treatment retained the expression of cell cycle regulatory proteins and the Oct4 in mESCs, which were blocked by compound 968 (a glutaminase inhibitor). In addition, Gln stimulated PI3K/Akt pathway, which subsequently elicited PKCϵ translocation to membrane without an influx of intracellular Ca(2+). Inhibition of Akt and PKC blocked Gln-induced Oct4 expression and proliferation. Gln also stimulated mTOR phosphorylation in a time-dependent manner, which abolished by PKC inhibition. Furthermore, Gln increased the cellular population of both Oct4 and bromodeoxyuridine positive cells, suggesting that Gln regulates self-renewal ability of mESCs. Gln induced a decrease in HDAC1, but not in HDAC2, which were blocked by PKC inhibitors. Gln treatment resulted in an increase in global histone acetylation and methylation. In addition, Gln significantly reduced methylation of the Oct4 promoter region through decrease in DNMT1 and DNMT3a expression, which were blocked by PKC and HDAC inhibitors. In conclusion, Gln stimulates mESC proliferation and maintains mESC undifferentiation status through transcription regulation via the Akt, PKCϵ, and mTOR signaling pathways.
authors.affiliation: a Department of Veterinary Physiology ; College of Veterinary Medicine, Seoul National University ; Seoul , Korea.
authors.forename: Jung Min
authors.initials: JM
authors.lastname: Ryu
authors.affiliation: b Medical Science Research Institute, Soonchunhyang University Seoul Hospital ; Seoul , Korea.
authors.forename: Sang Hun
authors.initials: SH
authors.lastname: Lee
authors.affiliation: c BK21 PLUS Program for Creative Veterinary Science Research and Research Institute for Veterinary Science, Seoul National University ; Seoul , Korea.|d Department of Anatomy and Cell Biology ; Korea Mouse Phenotyping Center (KMPC), College of Veterinary Medicine, Seoul National University ; Seoul , Korea.
authors.forename: Je Kyung
authors.initials: JK
authors.lastname: Seong
authors.affiliation: a Department of Veterinary Physiology ; College of Veterinary Medicine, Seoul National University ; Seoul , Korea.|c BK21 PLUS Program for Creative Veterinary Science Research and Research Institute for Veterinary Science, Seoul National University ; Seoul , Korea.
authors.forename: Ho Jae
authors.initials: HJ
authors.lastname: Han
mesh_terms: D000818:Animals; D000066673:Cell Self Renewal / Q000502:physiology*; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000378:metabolism*; D000090205:DNA Methyltransferase 3A; D015536:Down-Regulation / Q000187:drug effects / Q000502:physiology; D005973:Glutamine / Q000172:deficiency / Q000494:pharmacology*; D056284:Histone Deacetylase 1 / Q000378:metabolism*; D051379:Mice; D000066450:Mouse Embryonic Stem Cells / Q000187:drug effects / Q000378:metabolism*; D011493:Protein Kinase C / Q000378:metabolism*
chemical_list: C000715535:Dnmt3a protein, mouse; D005973:Glutamine; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases; D000090205:DNA Methyltransferase 3A; C000619381:Dnmt1 protein, mouse; D011493:Protein Kinase C; C484389:Hdac1 protein, mouse; D056284:Histone Deacetylase 1
keywords: Oct4; glutamine; mouse embryonic stem cells; proliferation; self-renewal