title: Shoot control of root development and nodulation is mediated by a receptor-like kinase.
abstract: In legumes, root nodule organogenesis is activated in response to morphogenic lipochitin oligosaccharides that are synthesized by bacteria, commonly known as rhizobia. Successful symbiotic interaction results in the formation of highly specialized organs called root nodules, which provide a unique environment for symbiotic nitrogen fixation. In wild-type plants the number of nodules is regulated by a signalling mechanism integrating environmental and developmental cues to arrest most rhizobial infections within the susceptible zone of the root. Furthermore, a feedback mechanism controls the temporal and spatial susceptibility to infection of the root system. This mechanism is referred to as autoregulation of nodulation, as earlier nodulation events inhibit nodulation of younger root tissues. Lotus japonicus plants homozygous for a mutation in the hypernodulation aberrant root (har1) locus escape this regulation and form an excessive number of nodules. Here we report the molecular cloning and expression analysis of the HAR1 gene and the pea orthologue, Pisum sativum, SYM29. HAR1 encodes a putative serine/threonine receptor kinase, which is required for shoot-controlled regulation of root growth, nodule number, and for nitrate sensitivity of symbiotic development.
authors.affiliation: Laboratory of Gene Expression, Department of Molecular Biology, University of Aarhus, Gustav Wieds Vej 10, 8000 Aarhus C, Denmark.
authors.forename: Lene
authors.initials: L
authors.lastname: Krusell
authors.forename: Lene H
authors.initials: LH
authors.lastname: Madsen
authors.forename: Shusei
authors.initials: S
authors.lastname: Sato
authors.forename: Grégoire
authors.initials: G
authors.lastname: Aubert
authors.forename: Aratz
authors.initials: A
authors.lastname: Genua
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Szczyglowski
authors.forename: Gérard
authors.initials: G
authors.lastname: Duc
authors.forename: Takakazu
authors.initials: T
authors.lastname: Kaneko
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tabata
authors.forename: Frans
authors.initials: F
authors.lastname: de Bruijn
authors.forename: Eloisa
authors.initials: E
authors.lastname: Pajuelo
authors.forename: Niels
authors.initials: N
authors.lastname: Sandal
authors.forename: Jens
authors.initials: J
authors.lastname: Stougaard
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D025461:Feedback, Physiological; D020869:Gene Expression Profiling; D017343:Genes, Plant / Q000235:genetics; D000070116:Lotus / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D009586:Nitrogen Fixation / Q000235:genetics; D018532:Pisum sativum / Q000201:enzymology / Q000235:genetics; D018517:Plant Roots / Q000201:enzymology / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology; D018520:Plant Shoots / Q000201:enzymology / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D012231:Rhizobium / Q000502:physiology; D013559:Symbiosis / Q000235:genetics
chemical_list: D017346:Protein Serine-Threonine Kinases