Format

Send to

Choose Destination
Development. 2019 Mar 15;146(6). pii: dev172411. doi: 10.1242/dev.172411.

A core mechanism for specifying root vascular patterning can replicate the anatomical variation seen in diverse plant species.

Author information

1
Centre for Plant Integrative Biology/School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK.
2
Institute of Biotechnology, HiLIFE/Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki 00014, Finland.
3
Graduate School of Science and Technology, Nara Institute of Science and Technology, Nara 630-0192, Japan.
4
Research Center in Biodiversity and Genetic Resources, Department of Biology, Faculty of Sciences, University of Porto, 4485-661 Vairão, Portugal.
5
School of Mathematical Sciences/Centre for Plant Integrative Biology, University of Nottingham, University Park, Nottingham NG7 2RD, UK.
6
Centre for Plant Integrative Biology/School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK anthony.bishopp@nottingham.ac.uk.

Abstract

Pattern formation is typically controlled through the interaction between molecular signals within a given tissue. During early embryonic development, roots of the model plant Arabidopsis thaliana have a radially symmetric pattern, but a heterogeneous input of the hormone auxin from the two cotyledons forces the vascular cylinder to develop a diarch pattern with two xylem poles. Molecular analyses and mathematical approaches have uncovered the regulatory circuit that propagates this initial auxin signal into a stable cellular pattern. The diarch pattern seen in Arabidopsis is relatively uncommon among flowering plants, with most species having between three and eight xylem poles. Here, we have used multiscale mathematical modelling to demonstrate that this regulatory module does not require a heterogeneous auxin input to specify the vascular pattern. Instead, the pattern can emerge dynamically, with its final form dependent upon spatial constraints and growth. The predictions of our simulations compare to experimental observations of xylem pole number across a range of species, as well as in transgenic systems in Arabidopsis in which we manipulate the size of the vascular cylinder. By considering the spatial constraints, our model is able to explain much of the diversity seen in different flowering plant species.

KEYWORDS:

Auxin; Cytokinin; Developmental biology; Multiscale modelling; Root biology; Vascular pattern

Conflict of interest statement

Competing interestsThe authors declare no competing or financial interests.

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center