Plasma Membranes Are Subcompartmentalized into a Plethora of Coexisting and Diverse Microdomains in Arabidopsis and Nicotiana benthamiana
Jarsch et al. (2014); The Plant Cell
18.03.2014
Iris K. Jarsch, Sebastian S.A. Konrad, Thomas F. Stratil, Susan L. Urbanus, Witold Szymanski, Pascal Braun, Karl-Heinz Braun and Thomas Ott
Abstract
Eukaryotic plasma membranes are highly compartmentalized structures. So far only few individual proteins that function in a wide range of cellular processes have been shown to segregate into micro-domains. However, the biological roles of most micro-domain associated proteins are unknown. Here we investigated the heterogeneity of distinct micro-domains and the complexity of their co-existence. This diversity was determined in living cells of intact multicellular tissues using twenty different marker proteins from Arabidopsis thaliana, mostly belonging to the Remorin protein family. These proteins associate with micro-domains at the cytosolic leaflet of the plasma membrane. We characterized these membrane domains and determined their lateral dynamics by extensive quantitative image analysis. Systematic co-localization experiments with an extended subset of marker proteins tested in 45 different combinations revealed the co-existence of highly distinct membrane domains on individual cell surfaces. These data open new perspectives and provide valuable tools to study lateral segregation of membrane proteins and their biological function in living plant cells. They also demonstrate that widely used biochemical approaches such as detergent resistant membranes (DRMs) cannot resolve this biological complexity of membrane compartmentalization in vivo.