Cell Wall Biochemistry Drives Pollen Tube Mechanics and Affects Growth Rate

Vogler, H.; Munglani, G.; Ndinyanka Fabrice, T.; Draeger, C.; Burri, J. T.; Eichenberger, C.; Knox, J. P.; Mollet, J.-C.; Nelson, B. J.; Herrmann, H. J.; Ringli, C.; Grossniklaus, U.

doi:10.1101/2021.11.09.467870

bioRxiv · 10.1101/2021.11.09.467870

Cell Wall Biochemistry Drives Pollen Tube Mechanics and Affects Growth Rate

Vogler, H.·Munglani, G.·Ndinyanka Fabrice, T.·Draeger, C.·Burri, J. T.·Eichenberger, C.·Knox, J. P.·Mollet, J.-C.·Nelson, B. J.·Herrmann, H. J.·Ringli, C.·Grossniklaus, U.

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Abstract

Pollen tubes maintain cell wall integrity as they rapidly grow towards the ovule, yet need to rupture at a precise moment to release the sperm cells. This biomechanical balance is critical for fertilization and relies on the interplay between turgor pressure and cell wall rigidity. How cell wall composition affects its mechanical properties is, however, not well understood. In this study, we combine experimental and simulation techniques to determine key mechanical parameters using Arabidopsis cell wall mutants. We integrated cellular force microscopy with a Finite Element Method-based model to predict growth rates of different mutant pollen tubes. The Finite Element Method-based model allowed us to quantify the effects of cell wall mutations on the time-independent turgor pressure and cell wall elasticity, while cellular force microscopy enabled determination of time-dependent viscoelastic properties of the cell wall. This novel approach can be applied across biological systems and advances mechanical studies of cell and tissue morphogenesis.

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Vogler, H., Munglani, G., Ndinyanka Fabrice, T., Draeger, C., Burri, J. T., Eichenberger, C., Knox, J. P., Mollet, J.-C., Nelson, B. J., Herrmann, H. J., Ringli, C., Grossniklaus, U.. 2021-11-11. Cell Wall Biochemistry Drives Pollen Tube Mechanics and Affects Growth Rate. https://doi.org/10.1101/2021.11.09.467870

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