1. Department of Cell Biology and Biochemistry (P.R.M., M.T.D., D.W.E., D.M.S.), Texas Tech University Health Sciences Center, Lubbock, Texas 79430
2. Department of Biochemistry (B.J.C.), University of Louisville School of Medicine, Louisville, Kentucky 40292
3. Institute de Génétique et de Biologie et Moléculaire et cellulaire (E.L., P.S.-C.), CNRS-INSERM, 67085 Strasbourg, France
4. Department of Cell Biology and Physiology (A.J.Z.), University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261