Intestinal enterocytes possess an apical array of densely packed microvilli known as the enterocyte brush border. Microvilli are so tightly packed in fully differentiated enterocytes that no free space remains between adjacent structures. The functional consequence of this arrangement is an immense capacity for housing membrane-associated nutrient processing and host defense machinery required for maintaining gut homeostasis. Despite being positioned at a critical physiological interface in the intestinal tract, there is little information on the how the brush border is formed. The goal of my research is to begin to elucidate the molecular mechanisms underlying assembly of the enterocyte brush border, specially focussing on the role that extracellular adhesion molecules from the protocadherin family play in regulating proper brush border formation. My research will contribute towards our understanding of the molecules and pathways that may be perturbed in GI diseases characterized by loss of brush border microvilli.