Plant Cell Huazhong Agricultural University
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

Plant Cell Advance Online Publication
Published on October 24, 2008; 10.1105/tpc.108.060913

This Article
Right arrow Full Text - TPC Advance Online Pub. (PDF)
Right arrow Supplemental Data
Right arrow All Versions of this Article:
20/10/2603    most recent
tpc.108.060913v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Lo, S.-F.
Right arrow Articles by Yu, S.-M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Lo, S.-F.
Right arrow Articles by Yu, S.-M.
Agricola
Right arrow Articles by Lo, S.-F.
Right arrow Articles by Yu, S.-M.

Received May 22, 2008
Returned for revision September 19, 2008
Accepted September 30, 2008

A Novel Class of Gibberellin 2-Oxidases Control Semidwarfism, Tillering, and Root Development in Rice

Shuen-Fang Lo 1, Show-Ya Yang 2, Ku-Ting Chen 3, Yue-Ie Hsing 4, Jan A.D. Zeevaart 5, Liang-Jwu Chen 2*, and Su-May Yu 3

1 Institute of Molecular Biology, National Chung-Hsing University, Taichung 402, Taiwan, Republic of China; Institute of Molecular Biology, Academia Sinica, Taipei 115, Taiwan, Republic of China
2 Institute of Molecular Biology, National Chung-Hsing University, Taichung 402, Taiwan, Republic of China
3 Institute of Molecular Biology, Academia Sinica, Taipei 115, Taiwan, Republic of China
4 Institute of Plant and Microbial Biology, Academia Sinica, Taipei 115, Taiwan, Republic of China
5 Department of Energy Plant Research Laboratory and Department of Plant Biology, Michigan State University, East Lansing, Michigan 48824-1312

* To whom correspondence should be addressed. E-mail: ljchen{at}nchu.edu.tw.

Gibberellin 2-oxidases (GA2oxs) regulate plant growth by inactivating endogenous bioactive gibberellins (GAs). Two classes of GA2oxs inactivate GAs through 2{beta}-hydroxylation: a larger class of C19 GA2oxs and a smaller class of C20 GA2oxs. In this study, we show that members of the rice (Oryza sativa) GA2ox family are differentially regulated and act in concert or individually to control GA levels during flowering, tillering, and seed germination. Using mutant and transgenic analysis, C20 GA2oxs were shown to play pleiotropic roles regulating rice growth and architecture. In particular, rice overexpressing these GA2oxs exhibited early and increased tillering and adventitious root growth. GA negatively regulated expression of two transcription factors, O. sativa homeobox 1 and TEOSINTE BRANCHED1, which control meristem initiation and axillary bud outgrowth, respectively, and that in turn inhibited tillering. One of three conserved motifs unique to the C20 GA2oxs (motif III) was found to be important for activity of these GA2oxs. Moreover, C20 GA2oxs were found to cause less severe GA-defective phenotypes than C19 GA2oxs. Our studies demonstrate that improvements in plant architecture, such as semidwarfism, increased root systems and higher tiller numbers, could be induced by overexpression of wild-type or modified C20 GA2oxs.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
ASPB Publications THE PLANT CELL PLANT PHYSIOLOGY
Copyright © 2008 by the American Society of Plant Biologists