Responses to auxin signals : an operating principle for dynamical sensitivity yet high resilience

RDP seminar by Silvia Grigolon from the Francis Crick Institute (London, UK)

Plants depend on the signalling of the phytohormone auxin for their development and for responding to environmental perturbations. The associated biomolecular signalling network involves a negative feedback on Aux/IAA proteins which mediate the influence of auxin (the signal) on the auxin response factor (ARF) transcription factors (the drivers of the response). To probe the role of this feedback, we consider alternative in silico signalling networks implementing different operating principles. By a comparative analysis, we find that the presence of a negative feedback allows the system to have a far larger sensitivity in its dynamical response to auxin and that this sensitivity does not prevent the system from being highly resilient. Given this insight, we build a new biomolecular signalling model for quantitatively describing such Aux/IAA and ARF responses and discuss how the outcomes of this model are relevant in the wider context of molecular networks robustness.

Date : Wednesday, November 27th
Time : 11am
Location : Place de l’Ecole

RDP host : Christophe Godin