Antagonistic action of strigolactone and cytokinin in bud outgrowth control

Dun, Elizabeth A., de Saint Germain, Alexandre, Rameau, Catherine and Beveridge, Christine A. (2012) Antagonistic action of strigolactone and cytokinin in bud outgrowth control. Plant Physiology, 158 1: 487-498. doi:10.1104/pp.111.186783

Author Dun, Elizabeth A.
de Saint Germain, Alexandre
Rameau, Catherine
Beveridge, Christine A.
Title Antagonistic action of strigolactone and cytokinin in bud outgrowth control
Journal name Plant Physiology   Check publisher's open access policy
ISSN 0032-0889
Publication date 2012-01
Year available 2011
Sub-type Article (original research)
DOI 10.1104/pp.111.186783
Volume 158
Issue 1
Start page 487
End page 498
Total pages 12
Place of publication Rockville, MD, United States
Publisher American Society of Plant Biologists
Collection year 2012
Language eng
Abstract Cytokinin (CK) has long been implicated as a promoter of bud outgrowth in plants, but exactly how this is achieved in coordination with other plant hormones is unclear. The recent discovery of strigolactones (SLs) as the long-sought branchinhibiting hormone allowed us to test how CK and SL coordinately regulate bud outgrowth in pea (Pisum sativum). We found that SL-deficient plants are more sensitive to stimulation of bud growth by low concentrations of locally applied CK than wildtype plants. Furthermore, in contrast with SL mutant plants, buds of wild-type plants are almost completely resistant to stimulation by CK supplied to the vasculature. Regardless of whether the exogenous hormones were supplied locally or to the xylem stream, SL and CK acted antagonistically on bud outgrowth. These data suggest that SLs do not affect the delivery of CK to axillary buds and vice versa. Rather, these data combined with dose-response experiments suggest that SLs and CK can act directly in buds to control their outgrowth. These hormones may converge at a common point in the bud outgrowth regulatory pathway. The expression of pea BRANCHED1, a TCP transcription factor expressed strongly in buds and thought to act downstream of SLs in shoot branching, is regulated by CK and SL without a requirement for protein synthesis and in a manner that correlates with observed bud growth responses.
Keyword Apical-Dominance
Axillary Buds
Auxin Transport
Growth Substance
Acts Downstream
Q-Index Code C1
Q-Index Status Confirmed Code
Institutional Status UQ
Additional Notes Published online before print October 2011.

Document type: Journal Article
Sub-type: Article (original research)
Collections: Official 2012 Collection
School of Biological Sciences Publications
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 86 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 97 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Tue, 31 Jan 2012, 00:01:07 EST by System User on behalf of School of Biological Sciences