A dWDR45 knock-out Drosophila model to decipher the role of autophagy in BPAN

Beta-propeller protein-associated neurodegeneration (BPAN) is a rare neurological disease characterized by severe cognitive and motor impairments. BPAN is caused by de novo pathogenic variants in the WDR45 gene on the X chromosome. WDR45 gene encodes the protein WDR45/WIPI4, a known regulator of autophagy. A defective autophagy has been observed in cellular models of BPAN disease and is associated with neurological dysfunctions in WDR45 knockout (KO) mice. However, it remains unclear whether the autophagic defect directly contributes to all WDR45 loss-induced phenotypes or whether other WDR45-dependent cellular functions are involved. To investigate this, we generated a CRISPR/Cas9-mediated KO of CG11975 ( dwdr45 KO), the Drosophila homolog of WDR45 . Our analysis revealed that dwdr45 KO flies display BPAN-like phenotypes, including impaired locomotor function, autophagy dysregulation and iron dyshomeostasis. Additionally, dwdr45 KO flies exhibit shorten lifespan compared to control flies. These findings demonstrate that dwdr45 KO fly is a relevant model for investigating the key cellular and molecular mechanisms underlying BPAN-associated phenotypes. Notably, induction of autophagy in dwdr45 KO flies partially rescued the shortened lifespan, but did not restore locomotor function. This suggests that defective autophagy contributes to some, but not all, aspects of the phenotypes resulting from loss of dwdr45 function.