Spatiotemporal brassinosteroid signaling and antagonism with auxin pattern stem cell dynamics in Arabidopsis roots.

ABSTRACT: The spatiotemporal balance between stem cell maintenance, proliferation, and differentiation determines the rate of root growth and is controlled by hormones, including auxin and brassinosteroid (BR). However, the spatial actions of BR and its interactions with auxin remain unclear in roots. Here, we show that oppositely patterned and antagonistic actions of BR and auxin maintain the stem cell balance and optimal root growth. We discover a pattern of low levels of nuclear-localized BR-activated transcription factor BZR1 in the stem cell niche and high BZR1 levels in the transition-elongation zone. This BZR1 pattern requires local BR catabolism and auxin synthesis, as well as BR signaling. Cell-type-specific expression of a constitutively active form of BZR1 confirms that the high and low l

SUBMITTER: Chaiwanon J 

PROVIDER: S-EPMC4415608 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature