The pea TCP transcription factor PsBRC1 acts downstream of strigolactones to control shoot branching
File(s)PsTB1 Braun et al. PlPh11 accepted MS version.pdf (1006.43 KB)
Accepted version
Author(s)
Type
Journal Article
Abstract
The function of PsBRC1, the pea (Pisum sativum) homolog of the maize (Zea mays) TEOSINTE BRANCHED1 and the Arabidopsis (Arabidopsis thaliana) BRANCHED1 (AtBRC1) genes, was investigated. The pea Psbrc1 mutant displays an increased shoot-branching phenotype, is able to synthesize strigolactone (SL), and does not respond to SL application. The level of pleiotropy of the SL-deficient ramosus1 (rms1) mutant is higher than in the Psbrc1 mutant, rms1 exhibiting a relatively dwarf phenotype and more extensive branching at upper nodes. The PsBRC1 gene is mostly expressed in the axillary bud and is transcriptionally up-regulated by direct application of the synthetic SL GR24 and down-regulated by the cytokinin (CK) 6-benzylaminopurine. The results suggest that PsBRC1 may have a role in integrating SL and CK signals and that SLs act directly within the bud to regulate its outgrowth. However, the Psbrc1 mutant responds to 6-benzylaminopurine application and decapitation by increasing axillary bud length, implicating a PsBRC1-independent component of the CK response in sustained bud growth. In contrast to other SL-related mutants, the Psbrc1 mutation does not cause a decrease in the CK zeatin riboside in the xylem sap or a strong increase in RMS1 transcript levels, suggesting that the RMS2-dependent feedback is not activated in this mutant. Surprisingly, the double rms1 Psbrc1 mutant displays a strong increase in numbers of branches at cotyledonary nodes, whereas branching at upper nodes is not significantly higher than the branching in rms1. This phenotype indicates a localized regulation of branching at these nodes specific to pea.
Date Issued
2011-11-01
Date Acceptance
2011-11-01
Citation
Plant Physiology, 2011, 158 (1), pp.225-238
ISSN
1532-2548
Publisher
American Society of Plant Biologists
Start Page
225
End Page
238
Journal / Book Title
Plant Physiology
Volume
158
Issue
1
Copyright Statement
© 2012 American Society of Plant Biologists. All rights reserved.
Subjects
Science & Technology
Life Sciences & Biomedicine
Plant Sciences
PLANT SCIENCES
AXILLARY BUD OUTGROWTH
APICAL DOMINANCE
ARABIDOPSIS-THALIANA
AUXIN TRANSPORT
CYTOKININ CONCENTRATION
MAIZE DOMESTICATION
FUNCTIONAL GENOMICS
MUTATIONAL ANALYSIS
CIRCADIAN CLOCK
RMS1 MUTANT
Arabidopsis Proteins
Cytokinins
Gene Expression Regulation, Plant
Isopentenyladenosine
Kinetin
Lactones
Molecular Sequence Data
Mutation
Peas
Plant Growth Regulators
Plant Proteins
Plant Shoots
Signal Transduction
Transcription Factors
Up-Regulation
Xylem
Plant Biology & Botany
06 Biological Sciences
07 Agricultural And Veterinary Sciences
Publication Status
Published