Abstract
Summary Plant survival depends on vascular tissues, which originate in a self‐organizing manner as strands of cells co‐directionally transporting the plant hormone auxin. The latter phenomenon (also known as auxin canalization) is classically hypothesized to be regulated by auxin itself via the effect of this hormone on the polarity of its own intercellular transport. Correlative observations supported this concept, but molecular insights remain limited.In the current study, we established an experimental system based on the model Arabidopsis thaliana, which exhibits auxin transport channels and formation of vasculature strands in response to local auxin application.Our methodology permits the genetic analysis of auxin canalization under controllable experimental conditions. By utilizing this opportunity, we confirmed the dependence of auxin canalization on a PIN‐dependent auxin transport and nuclear, TIR1/AFB‐mediated auxin signaling. We also show that leaf venation and auxin‐mediated PIN repolarization in the root require TIR1/AFB signaling.Further studies based on this experimental system are likely to yield better understanding of the mechanisms underlying auxin transport polarization in other developmental contexts.
Highlights
Plants possess superb abilities to adapt their development to the changing environment
(Mazur et al, 2016), we showed that stem vasculature regeneration after wounding was associated with the activation of nuclear auxin signaling and induction of PIN1 auxin transport channels
We wounded inflorescence stems of Col-0 as well as triple tir1afb1afb3 and tir1afb2afb3 mutants and assessed the extent of vasculature regeneration in them 6 d after wounding (DAW; Fig. 1a,b)
Summary
Plants possess superb abilities to adapt their development to the changing environment. One of them is their capacity to form organized vasculature, which occurs under normal (e.g. leaf venation or when nascent organs connect to the pre-existing vascular network) and traumatic (e.g. re-connection of broken vascular strands after wounding) conditions. The latter example occurs frequently within the ontogeny of higher plants (due to grazing or other types of mechanical stress) and is paramount to their survival. Observations of a similar correlation between auxin signaling and auxin transport polarization have been made during embryonic apical–basal axis establishment (Robert et al, 2013), shoot and root organogenesis (Benkova et al, 2003; Heisler et al, 2005; Bhatia et al, 2016) as well as unexpected process such as the termination of shoot gravitropic response (Rakusova et al, 2016)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
