National Institute for Basic Biology, National Institutes of Natural Sciences, Nishigonaka 38, Myodaiji, Okazaki 444-8585, Japan. uchiyama@nibb.ac.jp.|National Institute for Basic Biology, National Institutes of Natural Sciences, Nishigonaka 38, Myodaiji, Okazaki 444-8585, Japan. uchiyama@nibb.ac.jp.|National Institute for Basic Biology, National Institutes of Natural Sciences, Nishigonaka 38, Myodaiji, Okazaki 444-8585, Japan. uchiyama@nibb.ac.jp.|Section for Genetics and Evolutionary Biology (EVOGENE) and Centre for Epigenetics, Development and Evolution (CEDE), University of Oslo, Oslo, Norway. kamran@ibv.uio.no.