Skip to Main content Skip to Navigation
Theses

Interaction between turgor pressure and plasmodesmata permeability

Abstract : Plant cells are surrounded by the rigid cell wall that precludes developmental processes that are central in animal development, like cell migration and tissue rearrangement. Instead, plant development relies on cell division and expansion. The current paradigm assumes that cell expansion depends on the biomechanical properties of the cell wall and on the generation of turgor pressure. Plasmodesmata are membrane-lined channels that connect neighboring cells and allow free movement of molecules that are smaller than their diameter (i.e., permeability). It is known that plasmodesmal permeability changes during plant development and that these modifications can affect movement of sugars. Because of this, plasmodesmal permeability seems to be a good candidate for the regulation of turgor pressure during cell expansion, however, its contribution remains largely unexplored. In turn, previous studies suggest that plasmodesmata may respond to changes in turgor pressure. In this work we put forward the hypothesis that turgor pressure and plasmodesmal permeability may affect each other during plant development. We addressed this problem by, first, putting forward a network of interactions between different cellular and molecular factors that might mediate these feedbacks between turgor and plasmodesmata. Second, we generated a computational model to explore one direction of these interactions: the role of plasmodesmal permeability on turgor pressure regulation. Our model uses Lockhart's equations for irreversible cell expansion with addition of plasmodesmal-dependent fluxes of water and solutes. We used cotton fiber as a study system because it is a single cell without division that mostly increases in length. Furthermore, previous experimental studies in this system have correlated closure of plasmodesmata with peak values of turgor pressure. The results of our model suggest that plasmodesmal permeability is, indeed, a key factor in regulating turgor and cotton fiber growth. Moreover, we suggest that dynamical changes of plasmodesmal permeability are needed in order to recover turgor pressure behaviors that have been experimentally reported. Finally, we explored with our collaborators the potential contribution of plasmodesmal permeability in the evolution of complex multicellular plants using the "Dynamical Patterning Modules" (DPMs) framework. These ideas can be useful in understanding how plant body plans originated.
Complete list of metadatas

Cited literature [219 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-02631574
Contributor : Abes Star :  Contact
Submitted on : Wednesday, May 27, 2020 - 8:33:30 AM
Last modification on : Friday, May 29, 2020 - 3:31:36 AM

File

Hernandez_Valeria_2019LYSEN076...
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-02631574, version 1

Citation

Valeria Hernàndez Hernàndez. Interaction between turgor pressure and plasmodesmata permeability. Development Biology. Université de Lyon, 2019. English. ⟨NNT : 2019LYSEN076⟩. ⟨tel-02631574⟩

Share

Metrics

Record views

90

Files downloads

83