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Related Experiment Video

Updated: Jun 16, 2026

Interactive and Visualized Online Experimentation System for Engineering Education and Research

Interactive and Visualized Online Experimentation System for Engineering Education and Research

Published on: November 24, 2021

Mathematical modelling of the Aux/IAA negative feedback loop.

A M Middleton¹, J R King, M J Bennett

¹School of Mathematical Sciences, University of Nottingham, University Park, Nottingham, NG7 2RD, UK. alistair.middleton@nottingham.ac.uk

Bulletin of Mathematical Biology

|February 6, 2010

Summary

This summary is machine-generated.

Plant hormone auxin regulates development by inducing Aux/IAA genes. Mathematical modeling reveals that the ratio of Aux/IAA protein to mRNA turnover rates can cause oscillations in gene expression, impacting plant development.

Related Experiment Videos

Last Updated: Jun 16, 2026

Interactive and Visualized Online Experimentation System for Engineering Education and Research

Interactive and Visualized Online Experimentation System for Engineering Education and Research

Published on: November 24, 2021

Area of Science:

Plant biology
Molecular biology
Systems biology

Background:

The plant hormone auxin is crucial for diverse developmental processes.
Auxin induces Aux/IAA genes, which are part of negative feedback loops regulating auxin signaling.
Auxin's effect involves mediating the turnover of Aux/IAA proteins, disrupting these feedback loops.

Purpose of the Study:

To develop a mathematical model of a single Aux/IAA negative feedback loop in identical plant cells.
To investigate the dynamical regimes of this feedback loop across different parameter values.
To identify key parameters influencing the system's behavior and potential oscillations.

Main Methods:

Development of a mathematical model for a single Aux/IAA negative feedback loop.
Exploration of the model's parameter space to identify distinct dynamical regimes.
Analysis of the ratio between Aux/IAA protein and mRNA turnover rates as a critical parameter.

Main Results:

The model exhibits a single steady-state.
Depending on parameter values, the system can reach a stable-node, stable-spiral, or a stable limit cycle.
A sufficiently small ratio of Aux/IAA protein to mRNA turnover rates leads to oscillations in Aux/IAA expression.

Conclusions:

The ratio of turnover rates is a key determinant of Aux/IAA expression dynamics.
Oscillatory expression patterns are possible under specific turnover rate conditions.
These findings may help explain recent experimental observations in plant development and auxin signaling.