The Frohman Laboratory

The Frohman
Laboratory

Regulation of exocytosis, cell shape, and mitochondrial fusion by lipid signaling pathways

Our laboratory examines lipid signals that alter cell morphology, regulate mitochondrial fusion, and trigger subcellular trafficking of membrane vesicles during regulated exocytosis and endocytosis. Disease-related topics include neurodegenerative disease (Charcot-Marie Tooth syndrome), diabetes, cancer, and impaired phagocytic immune responses to pathogens.

The specific topic constitutes study of signaling pathways mediated by members of the superfamiles of enzymes known as Phospholipase D (PLD) and PI4P Kinase. Classic PLD is activated by a wide variety of agonists that signal through G-protein coupled or tyrosine kinase receptors. PLD has varied cellular roles including facilitating membrane vesicle trafficking and fusion of the vesicles into the plasma membrane during regulated exocytosis, and reorganizing the actin cytoskeleton. We are currently investigating roles for PLD and PI4P lipid kinase in actin cytoskeleton reorganization, myoblast differentiation and fusion, Glut-4 glucose transporter translocation, phagocytosis, and regulated exocytosis (insulin and histamine release). In addition, we are exploring a novel member of the PLD superfamily that localizes to mitochondria and regulates fusion, and the mechanisms through which diminished rates of fusion cause neurodegenerative disease.

Michael Frohman

Professor of Pharmacology