eIF4G1 and carboxypeptidase E axis dysregulation in O-GlcNAc transferase–deficient pancreatic β cells contributes to hyperproinsulinemia in mice — Mechanisms of hyperproinsulinemia in OGT deficient β-cells — eIF4G1 and carboxypeptidase E axis dysregulation in O-GlcNAc transferase–deficient pancreatic β-cells contributes to hyperproinsulinemia in mice — Mechanisms of hyperproinsulinemia in OGT-deficient β-cells