Wolfram syndrome 1 gene regulates pathways maintaining beta-cell health and survival

WFS1 is a causative gene for Wolfram syndrome, a rare neurodegenerative disorder characterized by juvenile-onset diabetes mellitus and optic nerve atrophy. Genetic proof of concept studies coupled with RNA-seq reveal that increasing WFS1 confers a survival advantage to cells under ER stress by activating Akt pathways and preserving ER homeostasis. This work reveals essential pathways regulated by WFS1 and therapeutic targets for Wolfram syndrome. Wolfram Syndrome 1 (WFS1) protein is an endoplasmic reticulum (ER) factor whose deficiency results in juvenile-onset diabetes secondary to cellular dysfunction and apoptosis. The mechanisms guiding beta-cell outcomes secondary to WFS1 function, however, remain unclear. Here, we show that WFS1 preserves normal beta-cell physiology by promoting insulin biosynthesis and negatively regulating ER stress. Depletion of Wfs1 in vivo and in vitro causes functional defects in glucose-stimulated insulin secretion and insulin content, triggering Chop-mediated apoptotic pathways. Genetic proof of concept studies coupled with RNA-seq reveal that increasing WFS1 confers a functional and a survival advantage to beta-cells under ER stress by increasing insulin gene expression and downregulating the Chop-Trib3 axis, thereby activating Akt pathways. Remarkably, WFS1 and INS levels are reduced in type-2 diabetic (T2DM) islets, suggesting that WFS1 may contribute to T2DM beta-cell pathology. Taken together, this work reveals essential pathways regulated by WFS1 to control beta-cell survival and function primarily through preservation of ER homeostasis.