In this talk I will present the two experimental systems that I have develloped during my PhD and postdoc : a magnetic pincher to probe the cortex of living animal cells and a microfluidic chip to study the growth of small plants. 

The magnetic pincher allowed us to physically measure the thickness of the actin cortex, to observe its dynamics in time, and to perform mechanical measurements. We observed fluctuations in the cortex thickness and showed that they were due to the contractile activity provided by myosin activity.

The second system is a microfluidic chip containing an array of traps used to isolate and observe a large number of seedlings from the landplant Marchantia polymorpha growing in medium. With the ability to quickly change the environement in the chip it became possible to perform osmotic steps to deform the plant and measure its hydromechanical properties. With this system we showed that both the mechanical properties and the porosity of the cell wall were part of the growth regulation system of the plant.