Alzheimer's disease (AD), the most common form of dementia, is characterized by the improper cleavage of amyloid precursor protein by a complex containing presenilin 1 (PSEN1) or presenilin 2 (PSEN2). Notably, PSEN1 and PSEN2 are strong genetic risk factors for heritable AD. However, 95% of AD cases currently have no known genetic cause. Recent work from the Valdmanis lab found PSEN2 isoform variations at the RNA level in sporadic AD. One such variation was the detection of differential 3'UTR lengths on the PSEN2 transcript. The 3'UTR is an important regulatory region that controls transcript maturation, stability, and abundance and is subject to environmental regulation. The length of this regulatory region is determined by RNA processing machinery during polyadenylation, and differences in this post-transcriptional process lead to differences in the 3'UTR length known as alternative polyadenylation (APA). APA may represent a functional mechanism by which PSEN2 regulation differs in AD. The goal of these studies is to understand the impact of PSEN2 APA on neuronal function. We hypothesize that the length of the 3'UTR on PSEN2 transcript aligns with phenotypic changes associated with AD. To test this hypothesis, we are cloning PSEN2 with short and long 3'UTRs to test the functional differences of PSEN2 APA in vitro. Our goal is to introduce the short and long PSEN2 3'UTR constructs in the cells, specifically, microglia, the brain's immune cells, which are heavily implicated in AD pathology. Then, we will visualize the subcellular location of these transcripts and test for altered amyloid beta processing, which is a pathological hallmark of AD. We anticipate detecting differences in regulation and subcellular localization between the short and long PSEN2 3'UTR transcripts. Elucidating the functional relevance of the short and long 3'UTR of the PSEN2 transcript will further our understanding of APA in AD.