spacer gif spacer gif spacer gif spacer gif ARCHIVE ANNOUNCEMENT! spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

First published online 13 March 2008
doi: 10.1242/dev.012807

Development 135, 1537-1546 (2008)
Published by The Company of Biologists 2008
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplementary Material
Right arrow All Versions of this Article:
dev.012807v1
135/8/1537    most recent
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
Google Scholar
Right arrow Articles by McKim, S. M.
Right arrow Articles by Haughn, G. W.
PubMed
Right arrow PubMed Citation
Right arrow Articles by McKim, S. M.
Right arrow Articles by Haughn, G. W.

The BLADE-ON-PETIOLE genes are essential for abscission zone formation in Arabidopsis

Sarah M. McKim1, Grethe-Elisabeth Stenvik2, Melinka A. Butenko2, Wenche Kristiansen2, Sung Ki Cho3, Shelley R. Hepworth1,*, Reidunn B. Aalen2 and George W. Haughn1,{dagger}

1 Department of Botany, University of British Columbia, Vancouver, British Columbia, V6T 1Z4, Canada.
2 Department of Molecular Biosciences, University of Oslo, PO Box 1041 Blindern, N-0316 Oslo, Norway.
3 Division of Biological Sciences, 303 Life Sciences Center, University of Missouri, Columbia, MO 65211, USA.

{dagger} Author for correspondence (e-mail: haughn{at}interchange.ubc.ca)

Accepted 6 February 2008

The Arabidopsis BLADE-ON-PETIOLE 1 (BOP1) and BOP2 genes encode redundant transcription factors that promote morphological asymmetry during leaf and floral development. Loss-of-function bop1 bop2 mutants display a range of developmental defects, including a loss of floral organ abscission. Abscission occurs along specialised cell files, called abscission zones (AZs) that develop at the junction between the leaving organ and main plant body. We have characterized the bop1 bop2 abscission phenotype to determine how BOP1 and BOP2 contribute to the known abscission developmental framework. Histological analysis and petal breakstrength measurements of bop1 bop2 flowers show no differentiation of floral AZs. Furthermore, vestigial cauline leaf AZs are also undifferentiated in bop1 bop2 mutants, suggesting that BOP proteins are essential to establish AZ cells in different tissues. In support of this hypothesis, BOP1/BOP2 activity is required for both premature floral organ abscission and the ectopic abscission of cauline leaves promoted by the INFLORESCENCE DEFICIENT IN ABSCISSION (IDA) gene under the control of the constitutive CaMV 35S promoter. Expression of several abscission-related marker genes, including IDA, is relatively unperturbed in bop1 bop2 mutants, indicating that these AZ genes respond to positional cues that are independent of BOP1/BOP2 activity. We also show that BOP1 and BOP2 promote growth of nectary glands, which normally develop at the receptacle adjacent to developing AZs. Taken together, these data suggest that BOP1/BOP2 activity is required for multiple cell differentiation events in the proximal regions of inflorescence lateral organs.

Key words: Abscission, BLADE-ON-PETIOLE, Flower development, INFLORESCENCE DEFICIENT IN ABSCISSION






© The Company of Biologists Ltd 2008