Abstract
Plant hormone auxin has critical roles in plant growth, dependent on its heterogeneous distribution in plant tissues. Exactly how auxin transport and developmental processes such as growth coordinate to achieve the precise patterns of auxin observed experimentally is not well understood. Here we use mathematical modelling to examine the interplay between auxin dynamics and growth and their contribution to formation of patterns in auxin distribution in plant tissues. Mathematical models describing the auxin-related signalling pathway, PIN and AUX1 dynamics, auxin transport, and cell growth in plant tissues are derived. A key assumption of our models is the regulation of PIN proteins by the auxin-responsive ARF-Aux/IAA signalling pathway, with upregulation of PIN biosynthesis by ARFs. Models are analysed and solved numerically to examine the long-time behaviour and auxin distribution. Changes in auxin-related signalling processes are shown to be able to trigger transition between passage- and spot-type patterns in auxin distribution. The model was also shown to be able to generate isolated cells with oscillatory dynamics in levels of components of the auxin signalling pathway which could explain oscillations in levels of ARF targets that have been observed experimentally. Cell growth was shown to have influence on PIN polarisation and determination of auxin distribution patterns. Numerical simulation results indicate that auxin-related signalling processes can explain the different patterns in auxin distributions observed in plant tissues, whereas the interplay between auxin transport and growth can explain the 'reverse-fountain' pattern in auxin distribution observed at plant root tips.
Original language | English |
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Article number | 17 |
Number of pages | 32 |
Journal | Bulletin of Mathematical Biology |
Volume | 82 |
Issue number | 2 |
Early online date | 22 Jan 2020 |
DOIs | |
Publication status | Published - Feb 2020 |
Keywords
- Mathematical modelling of signalling processes
- Transport of hormone auxin in plant tissues
- Plant growth and polarity of auxin-efflux carrier protein PIN
ASJC Scopus subject areas
- General Agricultural and Biological Sciences
- General Environmental Science
- General Mathematics
- General Biochemistry,Genetics and Molecular Biology
- General Neuroscience
- Pharmacology
- Computational Theory and Mathematics
- Immunology