Plant recognition of symbiotic bacteria requires two LysM receptor-like kinases.
Although most higher plants establish a symbiosis with arbuscular mycorrhizal fungi, symbiotic nitrogen fixation with rhizobia is a salient feature of legumes. Despite this host range difference, mycorrhizal and rhizobial invasion shares a common plant-specified genetic programme controlling the early host interaction. One feature distinguishing legumes is their ability to perceive rhizobial-specific signal molecules. We describe here two LysM-type serine/threonine receptor kinase genes, NFR1 and NFR5, enabling the model legume Lotus japonicus to recognize its bacterial microsymbiont Mesorhizobium loti. The extracellular domains of the two transmembrane kinases resemble LysM domains of peptidoglycan- and chitin-binding proteins, suggesting that they may be involved directly in perception of the rhizobial lipochitin-oligosaccharide signal. We show that NFR1 and NFR5 are required for the earliest physiological and cellular responses to this lipochitin-oligosaccharide signal, and demonstrate their role in the mechanism establishing susceptibility of the legume root for bacterial infection.
Radutoiu
Simona
S
Laboratory of Gene Expression, Department of Molecular Biology, University of Aarhus, Gustav Wieds Vej 10, 8000 Aarhus C, Denmark.
Madsen
Lene Heegaard
LH
Madsen
Esben Bjørn
EB
Felle
Hubert H
HH
Umehara
Yosuke
Y
Grønlund
Mette
M
Sato
Shusei
S
Nakamura
Yasukazu
Y
Tabata
Satoshi
S
Sandal
Niels
N
Stougaard
Jens
J
D000595:Amino Acid Sequence; D001665:Binding Sites; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant / Q000235:genetics; D005816:Genetic Complementation Test; D006863:Hydrogen-Ion Concentration; D000070116:Lotus / Q000201:enzymology* / Q000235:genetics / Q000382:microbiology*; D008969:Molecular Sequence Data; D009154:Mutation; D009586:Nitrogen Fixation; D010641:Phenotype; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000382:microbiology; D011401:Promoter Regions, Genetic / Q000235:genetics; 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; D013559:Symbiosis
D018076:DNA, Complementary; D010940:Plant Proteins; D012333:RNA, Messenger; D017346:Protein Serine-Threonine Kinases