Quantification of Mechanical Forces and Physiological Processes Involved in Pollen Tube Growth Using Microfluidics and Microrobotics

  • Jan T. Burri
  • Gautam Munglani
  • Bradley J. Nelson
  • Ueli Grossniklaus
  • Hannes VoglerEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 2160)


Pollen tubes face many obstacles on their way to the ovule. They have to decide whether to navigate around cells or penetrate the cell wall and grow through it or even within it. Besides chemical sensing, which directs the pollen tubes on their path to the ovule, this involves mechanosensing to determine the optimal strategy in specific situations. Mechanical cues then need to be translated into physiological signals, which eventually lead to changes in the growth behavior of the pollen tube. To study these events, we have developed a system to directly quantify the forces involved in pollen tube navigation. We combined a lab-on-a-chip device with a microelectromechanical systems-based force sensor to mimic the pollen tube’s journey from stigma to ovary in vitro. A force-sensing plate creates a mechanical obstacle for the pollen tube to either circumvent or attempt to penetrate while measuring the involved forces in real time. The change of growth behavior and intracellular signaling activities can be observed with a fluorescence microscope.

Key words

Pollen tube (PT) Growth Force sensor Perceptive force Penetrative force Lab-on-a-chip (LOC) Microelectromechanical system (MEMS) Calcium (Ca2+Imaging Fluorescence 


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2020

Authors and Affiliations

  • Jan T. Burri
    • 1
  • Gautam Munglani
    • 2
  • Bradley J. Nelson
    • 1
  • Ueli Grossniklaus
    • 2
  • Hannes Vogler
    • 2
    Email author
  1. 1.Multi-Scale Robotics Lab, Department of Mechanical and Process EngineeringETH ZurichZurichSwitzerland
  2. 2.Department of Plant and Microbial Biology and Zurich-Basel Plant Science CenterUniversity of ZurichZurichSwitzerland

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