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

Elife. 2014 Sep 16;3:e03115. doi: 10.7554/eLife.03115.


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.

Keywords: arabidopsis; cell biology; plant biology; plant nutrition; polarity; root biology.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / genetics
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / genetics*
  • Arabidopsis Proteins / metabolism
  • Biological Transport / genetics
  • COP9 Signalosome Complex
  • Cell Differentiation / genetics
  • Diffusion
  • Gene Expression Profiling
  • Gene Expression Regulation, Plant
  • Homeostasis / genetics*
  • Lipids / biosynthesis
  • Microscopy, Confocal
  • Mutation*
  • Nuclear Proteins / genetics*
  • Nuclear Proteins / metabolism
  • Oligonucleotide Array Sequence Analysis
  • Plant Roots / cytology
  • Plant Roots / genetics*
  • Plant Roots / metabolism
  • Plants, Genetically Modified
  • Potassium / metabolism
  • Protein Kinases / genetics*
  • Protein Kinases / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Water / metabolism


  • Arabidopsis Proteins
  • Lipids
  • Nuclear Proteins
  • Water
  • suberin
  • Protein Kinases
  • COP9 Signalosome Complex
  • Potassium

Grant support

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.