Cell wall constrains lateral diffusion of plant plasma membrane proteins Journal Article

Author(s): Martinière, Alexandre; Lavagi, Irene; Nageswaran, Gayathri; Rolfe, Daniel J; Maneta-Peyret, Lilly; Luu, Doan-Trung; Botchway, Stanley W; Webb, Stephen E; Mongrand, Sebastien; Maurel, Christophe; Martin-Fernandez, Marisa L; Kleine-Vehn, Jürgen; Friml, Jiří; Moreau, Patrick; Runions, John
Article Title: Cell wall constrains lateral diffusion of plant plasma membrane proteins
Abstract: A cell membrane can be considered a liquid-phase plane in which lipids and proteins theoretically are free to diffuse. Numerous reports,however, describe retarded diffusion ofmembrane proteins in animal cells. This anomalous diffusion results from a combination of structuring factors including protein-protein interactions, cytoskeleton corralling, and lipid organization into microdomains. In plant cells, plasma-membrane (PM) proteins have been described as relatively immobile, but the control mechanisms that structure the PM have not been studied. Here, we use fluorescence recovery after photobleaching to estimate mobility of a set of minimal PM proteins. These proteins consist only of a PM-anchoring domain fused to a fluorescent protein, but their mobilities remained limited, as is the case for many full-length proteins. Neither the cytoskeleton nor membrane microdomain structure was involved in constraining the diffusion of these proteins. The cell wall, however, was shown to have a crucial role in immobilizing PM proteins. In addition, by single-molecule fluorescence imaging we confirmed that the pattern of cellulose deposition in the cell wall affects the trajectory and speed ofPMprotein diffusion. Regulation ofPMprotein dynamics by the plant cell wall can be interpreted as a mechanism for regulating protein interactions in processes such as trafficking and signal transduction.
Journal Title: PNAS
Volume: 109
Issue 31
ISSN: 1091-6490
Publisher: National Academy of Sciences  
Date Published: 2012-07-31
Start Page: 12805
End Page: 12810
DOI: 10.1073/pnas.1202040109
Open access: no