1. Mayo Clinic (D.J.R., G.E., T.E.H., K.M.W., S.K., T.C.S.), Rochester, Minnesota 55905
2. Department of Nutrition and Exercise Sciences (U.T.I., J.C.H., R.T.T.), Oregon State University, Corvallis, Oregon
3. Department of Cell Biology (J.P.L., B.W.O.), Baylor College of Medicine, Houston, Texas 77030