Terry O'Halloran, Associate Professor
Section of Molecular Cell and Developmental Biology
235 Patterson Building
Research Interests: membrane trafficking, cellular signalling, clathrin, small GTPases, rabs, endocytosis, cell motility
CLICK HERE FOR THE WEBPAGE FOR MOLECULAR 190, FALL 2002
Living Cell Expressing Clathrin labeled with Green Fluorescent Protein
The membranes of eukarytoic cells are in continual flux, trafficking receptors and other proteins to their appropriate intracellular destinations. This process is important to signal transduction, cancer, and development. The overall goal of my lab is to understand how membrane traffic is regulated in normal cells and how this process goes awry in diseased cells. Our research is designed to identify and understand the cellular proteins that form, direct and regulate membrane traffic. One strategy is to create "knock-out" cell lines with specific mutations in gene products that mediate membrane traffic. We then test physiological function in these mutant cells. A complementary strategy is to tag normal and mutant proteins with the fluorescent tag, Green Fluorescent Protein, and then examine the dynamic distribution of these proteins in living cells.
Currently, we are focusing on the proteins that form the structural coat of endocytic membranes, the clathrin coat, and on rabs, small GTPases thought to regulate the fusion or budding of endocytic membrane. To approach this problem we use a combination of molecular biology, genetics and time-lapse fluorescence microscopy to image living cells. As model systems, we use the single-celled organism, Dictyostelium discoideum, and mammalian cells grown in tissue culture.
Damer, C.K., and O'Halloran, T.J. Spatially regulated recruitment of clathrin to the plasma membrane during capping and cell translocation. Molecular Biology of the Cell. 11: 2151-2159 (2000)
Wessels, D., Reynolds, J., Johnson, O.,Voss, E.,Burns, R., Daniels, K.,Garrard, E., O'Halloran, T., Soll,D.R. Clathrin plays a novel role in the regulation of cell polarity, pseudopod formation, uropod stability and motility in Dictyostelium. Journal of Cell Science. 113: (2000)
O'Halloran, TJ Cytokinesis and Membrane Traffic. Traffic. (December, 2000)
Dragoi IA, and O'Halloran TJ. Cloning and Characterization of a Dictyostelium Gene encoding a Small GTPase of the Rab11 Family. J. of Cellular Biochemistry. 70: 29-37 (1998)
Niswonger ML, and O'Halloran TJ. A novel role for clathrin in cytokinesis. Proc. Natl. Acad. Sci. USA. 94:8575-8578 (1997)
Niswonger ML, and O'Halloran TJ. Clathrin is essential for spore-cell differentiation but is not required for stalk-cell differentiation. Development. 124:443-451 (1997)
Riddelle-Spencer K, and O'Halloran TJ. Purification of clathrin from Dictyostelium discoideum and characterization of the clathrin light chain. Protein Expression and Purification 11:250-256. (1997).
Ruscetti T, Cardelli JA, Niswonger ML, and O'Halloran TJ. The clathrin heavy chain functions in sorting and secretion of lysosomal enzymes in Dictyostelium discoideum. Journal of Cell Biology. 126:343-352 (1994)