BRX promotes Arabidopsis shoot growth

0351019 - ÚEB 2011 RIV GB eng J - Journal Article
Beuchat, J. - Scacchi, E. - Tarkowská, Danuše - Ragni, L. - Strnad, Miroslav - Hardtke, C.S.
BRX promotes Arabidopsis shoot growth.
New Phytologist. Roč. 188, č. 1 (2010), s. 23-29. ISSN 0028-646X. E-ISSN 1469-8137
R&D Projects: GA AV ČR IAA400550801
Institutional research plan: CEZ:AV0Z50380511
Keywords : Arabidopsis * auxin * brassinosteroid
Subject RIV: CC - Organic Chemistry
Impact factor: 6.516, year: 2010

BREVIS RADIX (BRX) has been identified through a loss-of-function allele in the Umkirch-1 accession in a natural variation screen for Arabidopsis root growth vigor. Physiological and gene expression analyses have suggested that BRX is rate limiting for auxin-responsive gene expression by mediating cross-talk with the brassinosteroid pathway, as impaired root growth and reduced auxin perception of brx can be (partially) rescued by external brassinosteroid application. Using genetic tools, we show that brx mutants also display significantly reduced cotyledon and leaf growth. Furthermore, reciprocal grafting experiments between mutant and complemented brx shoot scions and root stocks suggest that the shoot phenotypes are not an indirect consequence of the root phenotype. In summary, our results demonstrate a ubiquitous, although quantitatively variable role of BRX in modulating the growth rate in both the root and shoot.
Permanent Link: http://hdl.handle.net/11104/0190863