Yuma Ito1, Akatsuki Kimura2,3. 1. School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho, Midori, Yokohama, 226-8501, Japan. 2. Cell Architecture Laboratory, Department of Chromosome Science, National Institute of Genetics, Mishima, 411-8540, Japan. akkimura@nig.ac.jp. 3. Department of Genetics, School of Life Science, The Graduate University for Advanced Studies, SOKENDAI, Mishima, 411-8540, Japan. akkimura@nig.ac.jp.