Evolution and regulation of the Lotus japonicus LysM receptor gene family.
LysM receptor kinases were identified as receptors of acylated chitin (Nod factors) or chitin produced by plant-interacting microbes. Here, we present the identification and characterization of the LysM receptor kinase gene (Lys) family (17 members) in Lotus japonicus. Comprehensive phylogenetic analysis revealed a correlation between Lys gene structure and phylogeny. Further mapping coupled with sequence-based anchoring on the genome showed that the family has probably expanded by a combination of tandem and segmental duplication events. Using a sliding-window approach, we identified distinct regions in the LysM and kinase domains of recently diverged Lys genes where positive selection may have shaped ligand interaction. Interestingly, in the case of NFR5 and its closest paralog, LYS11, one of these regions coincides with the predicted Nod-factor binding groove and the suggested specificity determining area of the second LysM domain. One hypothesis for the evolutionary diversification of this receptor family in legumes is their unique capacity to decipher various structures of chitin-derived molecules produced by an extended spectrum of interacting organisms: symbiotic, associative, endophytic, and parasitic. In a detailed expression analysis, we found several Lotus Lys genes regulated not only during the symbiotic association with Mesorhizobium loti but also in response to chitin treatment.
Lohmann
Gitte Vestergaard
GV
Centre for Carbohydrate Recognition and Signalling, MBI, University of Aarhus, Gustav Wieds Vej 10, Aarhus C, Denmark.
Shimoda
Yoshikazu
Y
Nielsen
Mette Wibroe
MW
Jørgensen
Frank Grønlund
FG
Grossmann
Christina
C
Sandal
Niels
N
Sørensen
Kirsten
K
Thirup
Søren
S
Madsen
Lene Heegaard
LH
Tabata
Satoshi
S
Sato
Shusei
S
Stougaard
Jens
J
Radutoiu
Simona
S
D001483:Base Sequence; D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D019143:Evolution, Molecular; D000070116:Lotus / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D005810:Multigene Family; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism*; D016415:Sequence Alignment
D010940:Plant Proteins