[1] Scripps Res Inst, Dept Mol Biol, La Jolla, CA 92037 USA
[2] Scripps Res Inst, Skaggs Inst Chem Biol, La Jolla, CA 92037 USA
[3] Univ Calif San Diego, Cell & Dev Biol Sect, Div Biol Sci, La Jolla, CA 92093 USA
[4] Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA
[5] Univ Calif Riverside, Dept Bot & Plant Sci, Ctr Plant Cell Biol, Riverside, CA 92521 USA