1. Howard Florey Institute of Experimental Physiology and Medicine (C.S.S., I.M., R.A.D.B., S.L.L., G.W.T.), University of Melbourne, Victoria 3010, Australia
2. Connetics Corporation (E.N.U., J.M.), Palo Alto, California 94303
3. Baker Heart Research Institute (X.-J.D.), Melbourne, Victoria 8008, Australia