LysM domain receptor kinases regulating rhizobial Nod factor-induced infection.
The rhizobial infection of legumes has the most stringent demand toward Nod factor structure of all host responses, and therefore a specific Nod factor entry receptor has been proposed. The SYM2 gene identified in certain ecotypes of pea (Pisum sativum) is a good candidate for such an entry receptor. We exploited the close phylogenetic relationship of pea and the model legume Medicago truncatula to identify genes specifically involved in rhizobial infection. The SYM2 orthologous region of M. truncatula contains 15 putative receptor-like genes, of which 7 are LysM domain-containing receptor-like kinases (LYKs). Using reverse genetics in M. truncatula, we show that two LYK genes are specifically involved in infection thread formation. This, as well as the properties of the LysM domains, strongly suggests that they are Nod factor entry receptors.
Limpens
Erik
E
Laboratory of Molecular Biology, Department of Plant Sciences, Wageningen University, Dreijenlaan 3, 6703HA, Wageningen, Netherlands.
Franken
Carolien
C
Smit
Patrick
P
Willemse
Joost
J
Bisseling
Ton
T
Geurts
René
R
D000595:Amino Acid Sequence; D001483:Base Sequence; D015870:Gene Expression; D017343:Genes, Plant; D008024:Ligands; D008070:Lipopolysaccharides / Q000378:metabolism*; D029902:Medicago / Q000235:genetics / Q000382:microbiology / Q000502:physiology*; D008954:Models, Biological; D008969:Molecular Sequence Data; D009154:Mutation; D009586:Nitrogen Fixation; D018532:Pisum sativum; D010641:Phenotype; D018517:Plant Roots / Q000382:microbiology* / Q000502:physiology; D011494:Protein Kinases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D034622:RNA Interference; D015398:Signal Transduction; D016962:Sinorhizobium meliloti / Q000737:chemistry / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D013559:Symbiosis
D008024:Ligands; D008070:Lipopolysaccharides; C023023:lipid-linked oligosaccharides; D011494:Protein Kinases