314 Beyond proteinopathies: Direct RNA sequencing illuminates epitranscriptomic alterations in Alzheimer’s disease-related genes

Objectives/Goals: To date, no study has jointly profiled RNA isoforms and modifications associated with Alzheimer’s disease neuropathological changes (ADNC) in a human cohort. Therefore, the overall objective of this study is to identify and characterize RNA isoforms and modifications that associate with ADNC by leveraging long-read direct RNA sequencing. Methods/Study Population: This translational study will analyze human prefrontal cortex tissue from a well-defined cohort of 12 individuals. The cohort consists of six individuals with severe Alzheimer’s disease neuropathological changes and six age- and sex-matched non-demented controls. Leveraging long-read direct RNA sequencing, which uniquely quantifies both RNA isoform and modifications simultaneously, can provide novel insights into how severe Alzheimer’s disease neuropathological changes drive changes in RNA isoform expression patterns and alter RNA modifications contributing to isoform dysregulation. Results/Anticipated Results: My preliminary data from human prefrontal cortex (n=2) revealed pseudouridine sites, 1 of ~170 known RNA modifications, in Alzheimer’s disease-risk genes (APP, CLU, SORT1, and BIN1), supporting the need to map RNA modifications across Alzheimer’s disease-relevant isoforms. My central hypothesis is that severe Alzheimer’s disease neuropathological changes (ADNCs) drive transcriptomic and epitranscriptomic dysregulation by altering RNA isoforms. Thus, my two working hypotheses are 1) severe ADNC drives transcriptomic dysregulation of RNA isoforms and 2) severe ADNC drives epitranscriptomic dysregulation of RNA modifications. Discussion/Significance of Impact: This project will be the first to jointly profile RNA isoforms and modifications accounting for Alzheimer’s disease neuropathological changes, offering candidate regulatory targets for therapeutic development. Importantly, this research will equip me with an expertise in RNA biology, neurodegenerative diseases, and bioinformatics.