1. Department of Cell and Molecular Biology (A.B.K., E.T.M., M.P.F, J.C.J., M.H.-D.), Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
2. School of Molecular Biosciences (A.B.K., M.H.-D., E.A.S.), Washington State University, Pullman, Washington 99164
3. Department of Biochemistry and Molecular Biology (J.R.B.), Colorado State University, Fort Collins, Colorado 80523