1. Department of Life Sciences and Systems Biology University of Torino Torino 10125 Italy
2. Laboratory of Plant–Microbe Interactions (LIPM) INRA‐CNRS‐Toulouse University Castanet‐Tolosan 31326 France
3. Department of Life Sciences School of Agriculture Meiji University Kawasaki Kanagawa 214‐8571 Japan
4. National Institute for Basic Biology (NIBB)/SOKENDAI Nishigonaka 38, Myodaiji Okazaki Aichi 444‐8585 Japan
5. Division of Biological Science Graduate School of Science Nagoya University Nagoya Aichi 464‐8602 Japan