title: Local and systemic regulation of plant root system architecture and symbiotic nodulation by a receptor-like kinase.
abstract: In plants, root system architecture is determined by the activity of root apical meristems, which control the root growth rate, and by the formation of lateral roots. In legumes, an additional root lateral organ can develop: the symbiotic nitrogen-fixing nodule. We identified in Medicago truncatula ten allelic mutants showing a compact root architecture phenotype (cra2) independent of any major shoot phenotype, and that consisted of shorter roots, an increased number of lateral roots, and a reduced number of nodules. The CRA2 gene encodes a Leucine-Rich Repeat Receptor-Like Kinase (LRR-RLK) that primarily negatively regulates lateral root formation and positively regulates symbiotic nodulation. Grafting experiments revealed that CRA2 acts through different pathways to regulate these lateral organs originating from the roots, locally controlling the lateral root development and nodule formation systemically from the shoots. The CRA2 LRR-RLK therefore integrates short- and long-distance regulations to control root system architecture under non-symbiotic and symbiotic conditions.
authors.affiliation: Institut des Sciences du Végétal (ISV), CNRS, UPR2355, Gif-sur-Yvette, France.
authors.forename: Emeline
authors.initials: E
authors.lastname: Huault
authors.affiliation: Institut des Sciences du Végétal (ISV), CNRS, UPR2355, Gif-sur-Yvette, France.
authors.forename: Carole
authors.initials: C
authors.lastname: Laffont
authors.affiliation: Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma, United States of America.
authors.forename: Jiangqi
authors.initials: J
authors.lastname: Wen
authors.affiliation: Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma, United States of America.
authors.forename: Kirankumar S
authors.initials: KS
authors.lastname: Mysore
authors.affiliation: Institut des Sciences du Végétal (ISV), CNRS, UPR2355, Gif-sur-Yvette, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Ratet
authors.affiliation: INRA, UMR1347 Agroécologie, Dijon, France.
authors.forename: Gérard
authors.initials: G
authors.lastname: Duc
authors.affiliation: Institut des Sciences du Végétal (ISV), CNRS, UPR2355, Gif-sur-Yvette, France.
authors.forename: Florian
authors.initials: F
authors.lastname: Frugier
mesh_terms: D046913:Medicago truncatula / Q000235:genetics* / Q000254:growth & development / Q000382:microbiology; D018519:Meristem / Q000235:genetics / Q000254:growth & development / Q000382:microbiology; D010802:Phylogeny; D010940:Plant Proteins / Q000502:physiology*; D020794:Receptor Protein-Tyrosine Kinases / Q000502:physiology*; D012231:Rhizobium / Q000502:physiology; D053204:Root Nodules, Plant / Q000235:genetics* / Q000254:growth & development / Q000382:microbiology; D013559:Symbiosis
chemical_list: D010940:Plant Proteins; D020794:Receptor Protein-Tyrosine Kinases