Exploring the multifaceted functions of APPL in metabolism and memory using Drosophila melanogaster

Amyloid precursor protein (APP) is a single-pass transmembrane protein abundantly expressed in the central nervous system and implicated in familial Alzheimer's disease, a progressive neurodegenerative disorder that impairs memory. Here, we investigated the role of amyloid precursor protein-like (APPL) using the model organism Drosophila melanogaster. In this study, Appl null mutants exhibited a reduced lifespan under normal conditions and increased triglyceride levels, which were mitigated by metformin treatment. Additionally, taste-associative memory impairment in Appld mutants suggested APPL's role in memory formation, which was restored by curcumin supplementation. The Appld mutants also displayed reduced climbing ability, which was improved by supplementation with vitamins C (ascorbic acid) and B₂ (riboflavin). These findings suggest that APPL is involved in metabolic regulation, cognition, climbing activity, and aging in Drosophila melanogaster.