PROJECT SUMMARY/ABSTRACT Alcohol consumption during pregnancy may result in fetal alcohol spectrum disorders (FASD), with fetal alcohol syndrome (FAS) being the most severe form and manifesting with facial abnormalities. Less severe forms of FASD are associated with a wide range of neurocognitive deficits and are difficult to diagnose in the absence of facial characteristics. Prenatal alcohol exposure (PAE) produces systemic impacts on the developing fetus, but most studies have been conducted on neuronal-specific changes in the brain and their contribution to PAE- associated neurodevelopmental disorders. Very few PAE studies have explored alcohol-elicited alterations to the vasculature of the brain during development. microRNA-mediated mechanisms that result in alterations to the brain vasculature during PAE are unknown. Our preliminary studies indicate that miR-150-5p is upregulated in brain microvascular endothelial cells (BMVECs) during PAE. This results in a decrease in its regulatory targets, including vascular endothelial zinc finger 1 (Vezf1), a novel target we have identified, which is a critical regulator of vascular development. We have also tested the effects of miR-150-5p on endothelial cell function. We have used migration, tube formation, and permeability assays as a way to analyze angiogenesis and blood brain barrier integrity in vitro. Preliminary data indicated that overexpressing miR-150-5p decreased migration and tube formation, and it increased BMVEC permeability, while miR-150-5p inhibition did the opposite. Additionally, treating cells with alcohol resulted in an increase in miR-150-5p expression which also resulted in decreased migration and tube formation. Our preliminary studies underscore the importance of miR-150-5p on regulating endothelial cell behavior and the adverse effects alcohol has on endothelial cell function. Since microRNAs post- transcriptionally regulate many different mRNA targets, we hypothesized that miR-150-5p is inhibiting vascular targets to adversely affect vascular morphology and function in the cortex during PAE. The following aims will be investigated to test this hypothesis: 1) Identify targets that are inhibited by miR-150-5p in primary BMVECs during prenatal alcohol exposure, 2) Determine the effects of miR-150-5p inhibition and/or target overexpression on primary BMVECs from prenatal alcohol exposed embryos, and 3) Examine the in vivo effects of miR-150-5p inhibition and/or target interference on the developing cortical vasculature during PAE. Successful completion of the aims integrated in this project will provide a better understanding of vascular contributions in the pathology of PAE. In addition, support from the Ruth L. Kirschstein National Research Service Award Individual Predoctoral Fellowship to Promote Diversity in Health-Related Research will contribute significantly to my career trajectory towards independent research.