title: A receptor kinase gene of the LysM type is involved in legume perception of rhizobial signals.
abstract: Plants belonging to the legume family develop nitrogen-fixing root nodules in symbiosis with bacteria commonly known as rhizobia. The legume host encodes all of the functions necessary to build the specialized symbiotic organ, the nodule, but the process is elicited by the bacteria. Molecular communication initiates the interaction, and signals, usually flavones, secreted by the legume root induce the bacteria to produce a lipochitin-oligosaccharide signal molecule (Nod-factor), which in turn triggers the plant organogenic process. An important determinant of bacterial host specificity is the structure of the Nod-factor, suggesting that a plant receptor is involved in signal perception and signal transduction initiating the plant developmental response. Here we describe the cloning of a putative Nod-factor receptor kinase gene (NFR5) from Lotus japonicus. NFR5 is essential for Nod-factor perception and encodes an unusual transmembrane serine/threonine receptor-like kinase required for the earliest detectable plant responses to bacteria and Nod-factor. The extracellular domain of the putative receptor has three modules with similarity to LysM domains known from peptidoglycan-binding proteins and chitinases. Together with an atypical kinase domain structure this characterizes an unusual receptor-like kinase.
authors.affiliation: Laboratory of Gene Expression, Department of Molecular Biology, University of Aarhus, Gustav Wieds Vej 10, 8000 Aarhus C, Denmark.
authors.forename: Esben Bjørn
authors.initials: EB
authors.lastname: Madsen
authors.forename: Lene Heegaard
authors.initials: LH
authors.lastname: Madsen
authors.forename: Simona
authors.initials: S
authors.lastname: Radutoiu
authors.forename: Magdalena
authors.initials: M
authors.lastname: Olbryt
authors.forename: Magdalena
authors.initials: M
authors.lastname: Rakwalska
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Szczyglowski
authors.forename: Shusei
authors.initials: S
authors.lastname: Sato
authors.forename: Takakazu
authors.initials: T
authors.lastname: Kaneko
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tabata
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; D017343:Genes, Plant / Q000235:genetics; D005816:Genetic Complementation Test; D008070:Lipopolysaccharides / Q000378:metabolism / Q000494:pharmacology; D000070116:Lotus / Q000201:enzymology / Q000235:genetics / Q000382:microbiology / Q000502:physiology*; D008969:Molecular Sequence Data; D009154:Mutation; D018532:Pisum sativum / Q000235:genetics; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012231:Rhizobium / Q000502:physiology*; D015398:Signal Transduction / Q000187:drug effects; D013559:Symbiosis
chemical_list: D008070:Lipopolysaccharides; D010940:Plant Proteins; D012333:RNA, Messenger; D017346:Protein Serine-Threonine Kinases