Genome, Phenome, Environment, and Evolution of Land Plants
Okano, Yosuke , Aono, Naoki , Hiwatashi, Yuji , Murata, Takashi , Nishiyama, Tomoaki , Ishikawa, Takaaki , Kubo, Minoru , Hasebe, Mitsuyasu .
A polycomb repressive complex 2 gene regulates apogamy and likely played a role in the evolution of extended diploid generation and branching in land plants.
The life cycle of land plants alternates between a haploid multicellular gametophyte and a diploid multicellular sporophyte. The haploid generation is more prominent in basal land plants, bryophytes, whereas the diploid generation dominates in seed plants. Genes regulating the alteration of generations are mostly unknown. Apogamy is a process that cells of the gametophyte other than the egg cell initiate sporophyte development. We found that deletion of CURLY LEAF ortholog in the moss Physcomitrella patens caused apogamy. Side branch initial cells, which usually form protonema or gametophore apical cells, formed sporophyte apical cells. The induced apogamous sporophyte continuously grew with an indeterminately grown apical cell. Astonishingly, it formed branches and the morphology was similar to protracheophytes. An induction of exogenous PpCLF in the deletion mutant formed sporangium-like organs at the tip of branches. These results suggest that the evolution of regulatory networks of PpCLF was related to the extension of diploid generation and the branch formation in land plants.
Log in to add this item to your schedule
Hasebe Laboratory Web Page
Physcomitrella patens page/PHYSCObase
1 - National Institute for Basic Biology, Okazaki, 444-8585, Japan
2 - Kanazawa University, Advanced Science Research Center, Kanazawa, 920-0934, Japan
3 - Japan Science and Technology Agency, Explaratory Research for Advanced Technology, Okazaki, 444-8585, Japan
Presentation Type: Symposium or Colloquium Presentation
Location: Ballroom 2/Cliff Lodge - Level B
Date: Monday, July 27th, 2009
Time: 3:45 PM