1. Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
2. Laboratory of Protein Structure, International Institute of Molecular and Cell Biology, Warsaw, Poland
3. Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE, USA
4. Department of Botany, Graduate School of Science, Kyoto University, Kyoto, Japan