Aldolase-regulated G3BP1/2⁺ condensates control insulin mRNA storage in beta cells.

ABSTRACT: Upregulation of insulin mRNA translation upon hyperglycemia in pancreatic islet β-cells involves several RNA-binding proteins. Here, we found that G3BP1, a stress granule marker downregulated in islets of subjects with type 2 diabetes, binds to insulin mRNA in glucose concentration-dependent manner. We show in mouse insulinoma MIN6-K8 cells exposed to fasting glucose levels that G3BP1 and its paralog G3BP2 colocalize to cytosolic condensates with eIF3b, phospho-AMPKα^Thr172 and Ins1/2 mRNA. Glucose stimulation dissolves G3BP1⁺/2⁺ condensates with cytosolic redistribution of their components. The aldolase inhibitor aldometanib prevents the glucose- and pyruvate-induced dissolution of G3BP1⁺/2⁺ condensates, increases phospho-AMPKα^Thr

SUBMITTER: Quezada E 

PROVIDER: S-EPMC12216156 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature