Neurons exhibit a unique structural and functional compartmentalization, comprising dendrites and axons that can project long distances. Their transcriptome is characterized by a remarkable diversity of mRNA isoforms and non-coding RNAs. To diversify the 3' untranslated regions (3'UTRs) of mRNAs, neurons employ alternative RNA processing mechanisms. A striking example of such mechanism is a neuron-specific form of alternative polyadenylation (APA) that is conserved from flies to humans and involves the lengthening of 3'UTRs in hundreds of genes. However, the in vivo biological effects of neuron-specific 3'UTRs remain unexplored. Using Drosophila melanogaster as model organism, I aim to study the phenotypic and molecular consequences of disrupting the expression of these 3'UTRs and investigate their association with the unique post-transcriptional needs of neurons.