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bioRxiv · 10.1101/2022.06.14.495617

Dual role of Pectin Methyl Esterase activity for plant cell growth regulation.

Gallemi Rovira, M.·Montesinos Lopez, J. C.·Zarevski, N.·Pribyl, J.·Skladal, P.·Hannezo, E.·Benkova, E.
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Abstract

Acid-growth theory has been postulated in the 70s to explain the rapid elongation of cells in response to plant hormone auxin. More recently, it has been demonstrated that activation of the proton ATPs pump (H+-ATPs) promoting acidification of the apoplast is the principal mechanism through which hormones like auxin as well as brassinosteroids (BR) induce cell elongation. However, the impact of this acidification on the mechanical properties of the cell wall remained largely unexplored. Here, we use Atomic Force Microscopy (AFM) to demonstrate that acidification of apoplast is necessary and sufficient to induce cell elongation through cell wall relaxation. Moreover, we demonstrate that Pectin Methyl Esterase (PME) can induce both cell wall softening or stiffening in extracellular calcium dependent-manner and that tight control of PME activity is required for hypocotyl elongation.

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Gallemi Rovira, M., Montesinos Lopez, J. C., Zarevski, N., Pribyl, J., Skladal, P., Hannezo, E., Benkova, E.. 2022-06-15. Dual role of Pectin Methyl Esterase activity for plant cell growth regulation.. https://doi.org/10.1101/2022.06.14.495617

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