- 2013-:Professor, Graduate School of Science, University of Tokyo
- 2007-:Head, Division of Land Plants, Department of Botany
- 2004-2007:Head, Division of Cryptogams, Department of Botany
- 1996-2004:Senior Curator, Division of Cryptogams, Department of Botany
- 1995-2013:Associate Professor, Graduate School of Science, University of Tokyo
- 1993-1996:Curator, Division of Cryptogams, Department of Botany