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bioRxiv · 10.1101/184648

Glutamine metabolism regulates Th2 cell differentiation via the α-ketoglutarate-dependent demethylation of histone H3K27

Abstract

The acquisition of T cell functions seems to be closely linked to the reprogramming of the metabolic pathway. However, the impact of metabolic changes on the differentiation of helper T cell subsets remains unclear. We found that TCR-mediated activation of glutamine metabolism regulates Th2 cell differentiation via the supplementation of -ketogulutalate (-KG) and histone H3K27 demethylation. Deprivation of glutamine or pharmacological inhibition of glutamine metabolism blocks the induction of Th2 cell differentiation without affecting Stat6 phosphorylation. The methylation status of H3K27 at the Th2 cytokine gene locus was significantly increased in Th2 cells cultured under glutamine-deprived conditions. The inhibitory effect of glutamine-deprivation was antagonized by -KG, and the -KG-dependent induction of Th2 cell differentiation was reduced in utx- and jmjd3-deficient naive CD4 T cells. These findings show that the glutamine-a-ketoglutarate axis is crucial to regulating the epigenetic status at the Th2 cytokine gene locus and subsequent Th2 cell differentiation.

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Kuwahara, M., Izumoto, M., Honda, H., Inoue, K., Imai, Y., Suzuki, J., Maruyama, S., Yasukawa, M., Yamashita, M.. 2017-09-05. Glutamine metabolism regulates Th2 cell differentiation via the α-ketoglutarate-dependent demethylation of histone H3K27. https://doi.org/10.1101/184648

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