A surface morphology-based inference method for the cell wall elasticity profile in tip-growing cells.

Area of Science:

• Plant Biology
• Biophysics
• Cell Biology

Background:

• Plant development relies on cell morphology and growth, influenced by turgor pressure and cell wall extension.
• Tip-growing cells have well-studied vesicle and cytoskeleton localization, but cell wall elasticity spatial profiles remain under-explored.
• Existing methods for cell wall elasticity measurement are limited in tracking experimental elastic deformation.

Purpose of the Study:

• To introduce and validate a novel surface morphology-based method for measuring cell wall elasticity in tip-growing cells.
• To infer the bulk modulus distribution from cell surface triangulation using fluorescently labeled markers.
• To assess the robustness and requirements of the new method using simulated and experimental data from *Physcomitrium patens*.

Main Methods:

• Developed a new method to infer bulk modulus distribution from cell surface triangulation of experimental marker points.
• Utilized fluorescent labeling to track marker points on the cell surface.
• Validated the method by simulating experimental noise and *P. patens* morphology, and by analyzing elasticity distributions from sampled cells.

Main Results:

• A larger triangulation improved method robustness against experimental noise, consistent with theoretical predictions.
• Sufficient recovery of elasticity distribution was achieved with 10 sampled cells, provided elastic stretches were sufficiently high.
• A dimensionless map of inference error verified a spatial change in *P. patens* bulk modulus within two-fold.

Conclusions:

• The new surface morphology-based method enables comprehensive measurements of cell wall elasticity in tip-growing cells.
• This technique provides a key advancement for understanding tip cell growth and morphogenesis.
• The findings offer a foundation for future studies on mechanical properties governing plant cell development.