Signoretti Christina, Gupte Sachin A
Department of Pharmacology, New York Medical College, Valhalla, NY, USA, 10595.
bioRxiv. 2023 Mar 7:2023.03.06.531429. doi: 10.1101/2023.03.06.531429.
Recent advances have revealed the importance of epigenetic modifications to gene regulation and transcriptional activity. DNA methylation, a determinant of genetic imprinting and silencing of genes genome-wide, is known to be controlled by DNA methyltransferases (DNMT) and demethylases (TET) under disease conditions. However, the mechanism(s)/factor(s) influencing the expression and activity of DNMTs and TETs, and thus DNA methylation, in healthy vascular tissue is incompletely understood. Based on our recent studies, we hypothesized that glucose-6-phosphate dehydrogenase (G6PD) is a modifier of DNMT and TET expression and activity and an enabler of gene expression.
In aorta of CRISPR-edited rats with the Mediterranean G6PD variant we determined DNA methylation by whole-genome bisulfite sequencing, gene expression by RNA sequencing, and large artery stiffness by echocardiography.
Here, we documented higher expression of , , and in aortas from Mediterranean G6PD variant (a loss-of-function single nucleotide polymorphism) rats than their wild-type littermates. Concomitantly, we identified 17,618 differentially methylated loci genome-wide (5,787 hypermethylated loci, including down-regulated genes encoding inflammation- and vasoconstriction-causing proteins, and 11,827 hypomethylated loci, including up-regulated genes encoding smooth muscle cell differentiation- and fatty acid metabolism-promoting proteins) in aorta from G6PD as compared to wild-type rats. Further, we observed less large artery (aorta) stiffness in G6PD as compared to wild-type rats.
These results establish a noncanonical function of the wild-type G6PD and G6PD variant in the regulation of DNA methylation and gene expression in healthy vascular tissue and reveals G6PD variant contributes to reduce large artery stiffness.
近期的研究进展揭示了表观遗传修饰对基因调控和转录活性的重要性。DNA甲基化是全基因组范围内基因印记和基因沉默的决定因素，已知在疾病状态下受DNA甲基转移酶（DNMT）和去甲基酶（TET）控制。然而，在健康血管组织中影响DNMTs和TETs表达及活性进而影响DNA甲基化的机制/因素尚未完全明确。基于我们最近的研究，我们推测葡萄糖-6-磷酸脱氢酶（G6PD）是DNMT和TET表达及活性的调节因子，也是基因表达的促成因素。
在具有地中海G6PD变体的CRISPR编辑大鼠的主动脉中，我们通过全基因组亚硫酸氢盐测序确定DNA甲基化，通过RNA测序确定基因表达，并通过超声心动图确定大动脉僵硬度。
在此，我们记录了地中海G6PD变体（功能丧失型单核苷酸多态性）大鼠主动脉中DNMT1、DNMT3A和TET2的表达高于其野生型同窝仔鼠。同时，我们在G6PD大鼠的主动脉中全基因组范围内鉴定出17,618个差异甲基化位点（5,787个高甲基化位点，包括编码引起炎症和血管收缩的蛋白质的下调基因，以及11,827个低甲基化位点，包括编码促进平滑肌细胞分化和脂肪酸代谢的蛋白质的上调基因）。此外，与野生型大鼠相比，我们观察到G6PD大鼠的大动脉（主动脉）僵硬度较小。
这些结果确立了野生型G6PD和G6PD变体在健康血管组织中调节DNA甲基化和基因表达的非经典功能，并揭示G6PD变体有助于降低大动脉僵硬度。
