CLN5 deficiency impairs glucose uptake in Batten disease

CLN5 disease, a form of juvenile dementia within the neuronal ceroid lipofuscinosis (NCL), is associated with mutations in theCLN5gene encoding the lysosomal bis(monoacylglycero)phosphate (BMP) synthase, essential for BMP production and lysosomal function. Limited knowledge of cellular mechanisms and unclear drug targets hinder translating this to children’s treatment, which remains symptomatic. We developed and characterized a newcln5knock-out zebrafish model that replicates key features and molecular signatures of the human disease. Loss of Cln5 functionin vivoaltered axonal growth of retinal ON-bipolar cells revealing new disease features. Additionally, multi-omic analyzes at different developmental stages, revealed an impaired glucose metabolism as an original finding in NCL. This work demonstrates the profound metabolic impact of CLN5 dysfunction, offering a promising avenue toward targeted therapies for juvenile dementia.