A receptor-like kinase mutant with absent endodermal diffusion barrier displays selective nutrient homeostasis defects.

Alexandre Pfister (1) , Marie Barberon (1) , Julien Alassimone (1) , Lothar Kalmbach (1) , Yuree Lee (1) , Joop E M Vermeer (1) , Misako Yamazaki (1) , Guowei Li (2) , Christophe Maurel (2) , Junpei Takano (3) , Takehiro Kamiya (4) , David E Salt (4) , Daniele Roppolo (1) , Niko Geldner (1)

1 Department of Plant Molecular Biology
2 BPMP - Biochimie et Physiologie Moléculaire des Plantes
3 Research Faculty of Agriculture
4 Institute of Environmental and Biological Sciences

The endodermis represents the main barrier to extracellular diffusion in plant roots, and it is central to current models of plant nutrient uptake. Despite this, little is known about the genes setting up this endodermal barrier. In this study, we report the identification and characterization of a strong barrier mutant, schengen3 (sgn3). We observe a surprising ability of the mutant to maintain nutrient homeostasis, but demonstrate a major defect in maintaining sufficient levels of the macronutrient potassium. We show that SGN3/GASSHO1 is a receptor-like kinase that is necessary for localizing CASPARIAN STRIP DOMAIN PROTEINS (CASPs)--major players of endodermal differentiation--into an uninterrupted, ring-like domain. SGN3 appears to localize into a broader band, embedding growing CASP microdomains. The discovery of SGN3 strongly advances our ability to interrogate mechanisms of plant nutrient homeostasis and provides a novel actor for localized microdomain formation at the endodermal plasma membrane.

Mots clés: root biology; polarity; plant nutrition; plant biology; cell biology; arabidopsis

Domaines: Sciences du Vivant [q-bio]; Biologie végétale

Alexandre Pfister, Marie Barberon, Julien Alassimone, Lothar Kalmbach, Yuree Lee, et al.. A receptor-like kinase mutant with absent endodermal diffusion barrier displays selective nutrient homeostasis defects.. eLife, 2014, 3, pp.e03115. ⟨10.7554/eLife.03115⟩. ⟨hal-01120479⟩