|Laboratory of ORIGIN OF EUKARYOTE|
|Hisayoshi Nozaki (Associate Professor)|
Species taxonomy of eukaryotic algae based on morphology and molecular phylogeny; Origin of male and female as revealed by the comparative studies of the colonial Volvocales; Origin and macro-taxonomy of eukaryotic plants.
We welcome everyone who loves“lower eukaryotes”and is much interested in evolutionary biology.
We have two research objectives using living cultured materials of eukaryotic algae and protozoa. These cultures were basically established by ourselves based on the field-collected samples. Thus, we welcome field survey and go to everywhere to get interesting organisms.
One of our objectives is to construct natural taxonomic systems of species of eukaryotic algae and their relatives based on comparative morphology and molecular phylogeny. We have firstly construct a natural taxonomic system of species of eukaryotic algae based on the morphological and monophyletic species concept in the genus Chlorogonium (Nozaki et al. 1998, J. Phycol.). This taxonomic methodology has been applied to various green microalgae and the charalean genus Nitella (Sakayama et al. 2005, J. Phycol.).
The other is to resolve fundamental biological problems such as origin of male-female sexuality and origin and macro-taxonomy of eukaryotic plants. Recently, we have firstly demonstrated the evolutionary link between the dominant isogametic mating type (minus) and the “male” by determining the male-specific gene “OTOKOGI” (PlestMID) in the anisogamous volvocalean Pleodorina starrii (Nozaki et al. 2006, Curr. Biol.). This breakthrough provides an opportunity to address any number of extremely interesting questions regarding evolution of oogamy and the origins of male-female dichotomy.
Based on the
genome sequence data of the primitive red alga Cyanidioschyzon (e. g. Nozaki et al. 2007,
BMC Biol.), we resolved the nonmonophyly
of the primary photosynthetic eukaryotes (Archaeplastida) and proposed a new
taxonomic concept of plants, Plantae
emend. Nozaki et al. (2003, J. Mol. Evol.) or
Postdoctoral fellows: Hiroko KAWAI-TOYOOKA, Yuko MOGI
Graduate students: Yi YANG, Kaoru KAWAFUNE, Ryo MATSUZAKI, Nanako ISAKA, Rei MORI, Yoko ARAGAKI, Toshiyuki TAKAHASHI
Undergraduates: Rintato HIRAIDE
Guest Postdoctoral fellow: Masahiro SUZUKI (
Nozaki, H., Ohta, N., Morita, E. & Watanabe, M. M. 1998. Toward a natural system of species in Chlorogonium (Volvocales, Chlorophyta): a combined analysis of morphological and rbcL gene sequence data J. Phycol. 34: 1024-1037.
Nozaki, H., Misawa, K., Kajita, T., Kato, M., Nohara, S. and Watanabe, M. M. 2000. Origin and evolution of the colonial Volvocales (Chlorophyceae) as inferred from multiple, chloroplast gene sequences. Mol. Phylog. Evol. 17: 256-268.
Nozaki, H., Mori, T., Misumi, O., Matsunaga, S. and Kuroiwa, T. 2006. Males evolved from the dominant isogametic mating type. Curr. Biol. 16: R1018-R1020.
Nozaki, H., Takano, H., Misumi, O., Terasawa, K., Matuzaki, M., Maruyama, S., Nishida, K., Yagisawa, F., Yoshida, Y., Fujiwara, T., Takio, S., Tamura, K., Chung, S.-J., Nakamura, S., Kuroiwa, H., Tanaka, K., Sato, N. and Kuroiwa, T. 2007. A 100%-complete sequence reveals unusually simple genomic features in the hot spring red alga Cyanidioschyzon merolae. BMC Biology 5: 28.
Nozaki, H., Iseki, M., Hasegawa, M., Misawa, K., Nakada, T., Sasaki, N. and Watanabe, M. 2007. Phylogeny of primary photosynthetic eukaryotes as deduced from slowly evolving nuclear genes. Mol. Biol. Evol. 24: 1592-1595.
Ferris, P., Olson, B. J. S. C., De Hoff, P. L., Douglass, S., Casero Diaz-Cano, D., Prochnik, S., Geng, S., Rai, R., Grimwood, J., Schmutz, J., Nishii, I., Hamaji, T., Nozaki, H., Pellegrini, M., and Umen, J. G. 2010. Evolution of an expanded sex determining region in Volvox. Science 328: 351-354.