1. Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892.
2. Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892.
3. Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892.
4. Protein Expression Laboratory, Office of the Director, National Institutes of Health, Bethesda, MD 20892.