Skip to main content
eScholarship
Open Access Publications from the University of California

Dynamic mechanical responses of arabidopsis thylakoid membranes during PSII-specific illumination

  • Author(s): Clausen, CH
  • Brooks, MD
  • Li, TD
  • Grob, P
  • Kemalyan, G
  • Nogales, E
  • Niyogi, KK
  • Fletcher, DA
  • et al.

Published Web Location

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4017268/
No data is associated with this publication.
Abstract

Remodeling of thylakoid membranes in response to illumination is an important process for the regulation of photosynthesis. We investigated the thylakoid network from Arabidopsis thaliana using atomic force microscopy to capture dynamic changes in height, elasticity, and viscosity of isolated thylakoid membranes caused by changes in illumination. We also correlated the mechanical response of the thylakoid network with membrane ultrastructure using electron microscopy. We find that the elasticity of the thylakoid membranes increases immediately upon PSII-specific illumination, followed by a delayed height change. Direct visualization by electron microscopy confirms that there is a significant change in the packing repeat distance of the membrane stacks in response to illumination. Although experiments with Gramicidin show that the change in elasticity depends primarily on the transmembrane pH gradient, the height change requires both the pH gradient and STN7-kinase-dependent phosphorylation of LHCII. Our studies indicate that lumen expansion in response to illumination is not simply a result of the influx of water, and we propose a dynamic model in which protein interactions within the lumen drive these changes. © 2014 Biophysical Society.

Many UC-authored scholarly publications are freely available on this site because of the UC Academic Senate's Open Access Policy. Let us know how this access is important for you.

Item not freely available? Link broken?
Report a problem accessing this item