RT Journal Article
SR Electronic
T1 A microbially derived tyrosine sulfated peptide mimics a plant peptide hormone
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 116897
DO 10.1101/116897
A1 Rory N. Pruitt
A1 Anna Joe
A1 Weiguo Zhang
A1 Wei Feng
A1 Valley Stewart
A1 Benjamin Schwessinger
A1 José R. Dinneny
A1 Pamela C. Ronald
YR 2017
UL http://biorxiv.org/content/early/2017/03/14/116897.abstract
AB The biotrophic pathogen Xanthomonas oryzae pv. oryzae (Xoo) produces a sulfated peptide named RaxX, which shares similarity to peptides in the PSY (plant peptide containing sulfated tyrosine) family. We hypothesize that RaxX functionally mimics the growth stimulating activity of PSY peptides.Root length was measured in Arabidopsis and rice treated with synthetic RaxX peptides. We also used comparative genomic analysis and Reactive Oxygen Species (ROS) burst assay to evaluate the activity of RaxX and PSY peptides.Here we found that a synthetic sulfated RaxX derivative comprising 13 residues (RaxX13-sY), highly conserved between RaxX and PSY, induces root growth in Arabidopsis and rice in a manner similar to that triggered by PSY. We identified residues that are required for activation of immunity mediated by the rice XA21 receptor but that are not essential for root growth induced by PSY. Finally, we showed that a Xanthomonas strain lacking raxX is impaired in virulence.These findings suggest that RaxX serves as a molecular mimic of PSY peptides to facilitate Xoo infection and that XA21 has evolved the ability to recognize and respond specifically to the microbial form of the peptide.