Glucose-Dependent Regulation of NR2F2 Promoter and Influence of SNP-rs3743462 on Whole Body Insulin Sensitivity

Background: The Nuclear Receptor 2F2 (NR2F2/COUP-TFII) heterozygous knockout mice display low basal insulinemia and enhanced insulin sensitivity. We previously established that insulin represses NR2F2 gene expression in pancreatic β-cells. The cis-regulatory region of the NR2F2 promoter is unknown and its influence on metabolism in humans is poorly understood. The present study aimed to identify the regulatory regions that control NR2F2 gene transcription and to evaluate the effect of NR2F2 promoter variation on glucose homeostasis in humans. Methodology/Principal Findings: Regulation of the NR2F2 promoter was assessed using gene reporter assays, ChIP and gel shift experiments. The effects of variation at SNP rs3743462 in NR2F2 on quantitative metabolic traits were studied in two European prospective cohorts. We identified a minimal promoter region that down-regulates NR2F2 expression by attenuating HNF4α activation in response to high glucose concentrations. Subjects of the French DESIR population, who carried the rs3743462 T-to-C polymorphism, located in the distal glucose-responsive promoter, displayed lower basal insulin levels and lower HOMA-IR index. The C-allele at rs3743462 was associated with increased NR2F2 binding and decreased NR2F2 gene expression. Conclusions/Significance: The rs3743462 polymorphism affects glucose-responsive NR2F2 promoter regulation and thereby may influence whole-body insulin sensitivity, suggesting a role of NR2F2 in the control of glucose homeostasis in humans. © 2012 Boutant et al

COUP-TFII Controls Mouse Pancreatic β-Cell Mass through GLP-1-β-Catenin Signaling Pathways

Background: The control of the functional pancreatic beta-cell mass serves the key homeostatic function of releasing the right amount of insulin to keep blood sugar in the normal range. It is not fully understood though how beta-cell mass is determined

Rare variants in NR2F2 cause congenital heart defects in humans

Congenital heart defects (CHDs) are the most common birth defect worldwide and are a leading cause of neonatal mortality. Nonsyndromic atrioventricular septal defects (AVSDs) are an important subtype of CHDs for which the genetic architecture is poorly understood. We performed exome sequencing in 13 parent-offspring trios and 112 unrelated individuals with nonsyndromic AVSDs and identified five rare missense variants (two of which arose de novo) in the highly conserved gene NR2F2, a very significant enrichment (p = 7.7 × 10?7) compared to 5,194 control subjects. We identified three additional CHD-affected families with other variants in NR2F2 including a de novo balanced chromosomal translocation, a de novo substitution disrupting a splice donor site, and a 3 bp duplication that cosegregated in a multiplex family. NR2F2 encodes a pleiotropic developmental transcription factor, and decreased dosage of NR2F2 in mice has been shown to result in abnormal development of atrioventricular septa. Via luciferase assays, we showed that all six coding sequence variants observed in individuals significantly alter the activity of NR2F2 on target promoters