1. T. Kozasa, X. Jiang, P. M. Sternweis, W. D. Singer, A. G. Gilman, P. C. Sternweis, Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75235, USA.
2. M. J. Hart and G. Bollag, Onyx Pharmaceuticals, 3031 Research Drive, Richmond, CA 94806, USA.