1. Department of Botany, University of British Columbia, Vancouver, BC, Canada.
2. Department of Wood Science, University of British Columbia, Vancouver, BC, Canada.
3. Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
4. Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA.
5. Graduate School of Biological Sciences, Nara Institute of Science and Technology, Nara, Japan.
6. Department of Biological Sciences, Stanford University, Stanford, CA, USA.