Mechanical factors contributing to the Venus flytrap's rate-dependent response to stimuli

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Eashan Saikia - (Author)
  • Nino F. Laeubli - (Author)
  • Hannes Vogler - (Author)
  • Markus Rüggeberg - , ETH Zurich, Swiss Federal Laboratories for Materials Science and Technology (Empa) (Author)
  • Hans J. Herrmann - (Author)
  • Ingo Burgert - (Author)
  • Jan T. Burri - (Author)
  • Bradley J. Nelson - (Author)
  • Ueli Grossniklaus - (Author)
  • Falk K. Wittel - (Author)

Abstract

The sensory hairs of the Venus flytrap (Dionaea muscipula Ellis) detect mechanical stimuli imparted by their prey and fire bursts of electrical signals called action potentials (APs). APs are elicited when the hairs are sufficiently stimulated and two consecutive APs can trigger closure of the trap. Earlier experiments have identified thresholds for the relevant stimulus parameters, namely the angular displacement θ and angular velocity ω. However, these experiments could not trace the deformation of the trigger hair’s sensory cells, which are known to transduce the mechanical stimulus. To understand the kinematics at the cellular level, we investigate the role of two relevant mechanical phenomena: viscoelasticity and intercellular fluid transport using a multi-scale numerical model of the sensory hair. We hypothesize that the combined influence of these two phenomena and ω contribute to the flytrap’s rate-dependent response to stimuli. In this study, we firstly perform sustained deflection tests on the hair to estimate the viscoelastic material properties of the tissue. Thereafter, through simulations of hair deflection tests at different loading rates, we were able to establish a multi-scale kinematic link between ω and the cell wall stretch δ. Furthermore, we find that the rate at which δ evolves during a stimulus is also proportional to ω. This suggests that mechanosensitive ion channels, expected to be stretch-activated and localized in the plasma membrane of the sensory cells, could be additionally sensitive to the rate at which stretch is applied.

Details

Original languageEnglish
Pages (from-to)2287-2297
Number of pages11
JournalBiomechanics and modeling in mechanobiology
Volume20
Issue number6
Publication statusPublished - Dec 2021
Peer-reviewedYes
Externally publishedYes

External IDs

Scopus 85113410809
ORCID /0000-0002-6966-8311/work/142254807

Keywords

Keywords

  • Dionaea muscipula, Venus flytrap, Mechanotransduction, Multi-scale modelling, Ion channels, Sensory hair