title: A peptide hormone required for Casparian strip diffusion barrier formation in Arabidopsis roots.
abstract: Plants achieve mineral ion homeostasis by means of a hydrophobic barrier on endodermal cells called the Casparian strip, which restricts lateral diffusion of ions between the root vascular bundles and the soil. We identified a family of sulfated peptides required for contiguous Casparian strip formation in Arabidopsis roots. These peptide hormones, which we named Casparian strip integrity factor 1 (CIF1) and CIF2, are expressed in the root stele and specifically bind the endodermis-expressed leucine-rich repeat receptor kinase GASSHO1 (GSO1)/SCHENGEN3 and its homolog, GSO2. A mutant devoid of CIF peptides is defective in ion homeostasis in the xylem. CIF genes are environmentally responsive. Casparian strip regulation is not merely a passive process driven by root developmental cues; it also serves as an active strategy to cope with adverse soil conditions.
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Nakayama
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan.
authors.forename: Hidefumi
authors.initials: H
authors.lastname: Shinohara
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan.
authors.forename: Mina
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan.
authors.forename: Koki
authors.initials: K
authors.lastname: Baba
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan.
authors.forename: Mari
authors.initials: M
authors.lastname: Ogawa-Ohnishi
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan. matsu@bio.nagoya-u.ac.jp.
authors.forename: Yoshikatsu
authors.initials: Y
authors.lastname: Matsubayashi
mesh_terms: D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D004058:Diffusion; D017343:Genes, Plant; D006706:Homeostasis; D009154:Mutation; D036361:Peptide Hormones / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D011494:Protein Kinases / Q000378:metabolism*; D052584:Xylem / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D036361:Peptide Hormones; D011494:Protein Kinases; C528620:GASSHO1 protein, Arabidopsis; C528621:GASSHO2 protein, Arabidopsis