Elimination of human folypolyglutamate synthetase alters programming and plasticity of somatic cells

Abstract

Folates are vital cofactors for the regeneration of S-adenosyl methionine, which is the methyl source for DNA methylation, protein methylation, and other aspects of one-carbon (C1) metabolism. Thus, folates are critical for establishing and preserving epigenetic programming. Folypolyglutamate synthetase (FPGS) is known to play a crucial role in the maintenance of intracellular folate levels. Therefore, any modulation in FPGS is expected to alter DNA methylation and numerous other metabolic pathways. To explore the role of polyglutamylation of folate, we eliminated both isoforms of FPGS in human cells (293T), producing FPGS knockout (FPGS ko ) cells. The elimination of FPGS significantly decreased cell proliferation, with a major effect on oxidative phosphorylation and a lesser effect on glycolysis. We found a substantial reduction in global DNA methylation and noteworthy changes in gene expression related to C1 metabolism, cell division, DNA methylation, pluripotency, Glu metabolism, neurogenesis, and cardiogenesis. The expression levels of NANOG, octamer-binding transcription factor 4, and sex-determining region Y-box 2 levels were increased in the mutant, consistent with the transition to a stem cell-like state. Gene expression and metabolite data also indicate a major change in Glu and GABA metabolism. In the appropriate medium, FPGS ko cells can differentiate to produce mainly cells with characteristics of either neural stem cells or cardiomyocytes.-

Maternal genotypes of folate/one‐carbon metabolism gene variants and nonsyndromic cleft lip with or without cleft palate risk in Chile

“…Polyglutamate forms of folates cannot be expelled to the extracellular compartment, and FPGS activity is fundamental for intracellular folate retention [39]. Consequently, a human cell line with a null mutation in FPGS showed a decrease in its proliferation rate, which was related to a reduction in DNA methylation and suggesting that epigenetic alteration may explain differential expression patterns of genes related to cell division and differentiation [40].…”

Metabolic-epigenetic nexus in regulation of stem cell fate

“…Folic acid: Folic acid is first metabolized to dihydrofolate and then to tetrahydrofolate, taking part in DNA synthesis, influencing DNA and histone methylation[ 105 ]. Several studies have elucidated the role of folate metabolism in regulating of the epigenetic landscape of stem cells[ 114 , 115 ]. Li et al [ 116 ] have shown that folic acid deficiency in NSCs decreased cell proliferative capacity but increased apoptosis.…”

Amino Acid-Mediated Metabolism: A New Power to Influence Properties of Stem Cells

“…The status of cancer cells can be reprogrammed through metabolic remodeling while their dedifferentiation ability for the induced stem-like phenotype is maintained [20–22]. This capability of switching between differentiated somatic and stem cell states is called cell plasticity [23]. When performing tumor therapy, both genomic instability and microenvironment-driven selection support tumor heterogeneity and enable the development of resistant cells with stem-like properties because of cell plasticity [24].…”