†Present address: Department of Biology, Kyungpook National University, Daegu, South Korea.
The role of two LEAFY paralogs from Idahoa scapigera (Brassicaceae) in the evolution of a derived plant architecture
Article first published online: 8 JUN 2007
The Plant Journal
Volume 51, Issue 2, pages 211–219, July 2007
How to Cite
Sliwinski, M. K., Bosch, J. A., Yoon, H.-S., Balthazar, M. v. and Baum , D. A. (2007), The role of two LEAFY paralogs from Idahoa scapigera (Brassicaceae) in the evolution of a derived plant architecture. The Plant Journal, 51: 211–219. doi: 10.1111/j.1365-313X.2007.03148.x
- Issue published online: 8 JUN 2007
- Article first published online: 8 JUN 2007
- Received 8 November 2006; revised 5 March 2007; accepted 12 March 2007.
- Idahoa scapigera;
- evolutionary developmental biology;
- internode compression;
- rosette flowering;
- interspecies transformation
Idahoa scapigera produces solitary flowers in the axils of rosette leaves without elongation of the shoot axis, a rosette-flowering architecture. Previous work with one of the two I. scapigera LFY paralogs, IscLFY1, showed that this gene caused aerial flowering rosettes in Arabidopsis thaliana. In this paper, we report that after three generations IscLFY1 transgenic lines are phenotypically indistinguishable from wild-type Arabidopsis, indicating that IscLFY1 protein is able to replace normal LFY function. Additionally, we found that ectopic LFY expression late in development can phenocopy aspects of the aerial rosette phenotype, suggesting that shoot compression caused by IscLFY1 could be caused by localized overexpression of a functional IscLFY protein. We also characterized the expression and function of the second I. scapigera LFY paralog, IscLFY2, in A. thaliana. In contrast to IscLFY1, this paralog was expressed in floral meristems and the shoot apical meristem (SAM). In I. scapigera, LFY-specific antibodies detected high protein levels in developing flowers but not in the apex, suggesting trans-regulatory differences between I. scapigera and A. thaliana. Most IscLFY2 transgenic A. thaliana plants were indistinguishable from wild type, but in a minority of lines the SAM was converted to a terminal flower as would be expected from the reporter-expression pattern. Taken together these results show that both I. scapigera paralogs have conserved LFY function, both proteins can rescue lfy and both can modify inflorescence architecture in an A. thaliana background: either by affecting internode elongation (IscLFY1) or by causing homeotic conversion of shoots into flowers (IscLFY2).