RNA binding proteins (RBPs) govern post-transcriptional regulation. Most often they act through binding to the 3'untranslated region (3'UTR) of messenger RNA (mRNA). In neurons, due to alternative polyadenylation (APA) mediated by ELAV protein there is the use of distant polyadenylation site which results in transcripts lenghtening in the 3'UTR. Those long 3'UTRs have enhanced potential for RBPs and mRNA binding. This way RBPs can post-transcriptionally regulate mRNAs, influencing their stability, transport or translation. My project aims to understand post-transcriptional regulation of neuronal-specific 3'UTR sequences. Disturbances in post-transcriptional regulation have been associated to pathogenic states, therefore it is important to focus our research on the mechanisms underlying RBPs function. Since RBPs and long 3'UTRs are conserved from invertebrates to humans, I am using Drosophila melanogaster as my model organism.