1. G. S. Hotamisligil, Department of Nutrition, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115, USA.
2. R. S. Johnson, Department of Biology, University of California, San Diego, La Jolla, CA 92093, USA.
3. R. J. Distel, R. Ellis, B. M. Spiegelman, Dana Farber Cancer Institute and Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.
4. V. E. Papaioannou, Department of Genetics and Development, Columbia University, 701 West 168 Street, New York, NY 10032, USA.