RT Journal Article
SR Electronic
T1 An unconventional NOI/RIN4 domain of a rice NLR protein binds host EXO70 protein to confer fungal immunity
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 239400
DO 10.1101/239400
A1 Koki Fujisaki
A1 Yoshiko Abe
A1 Eiko Kanzaki
A1 Kazue Ito
A1 Hiroe Utsushi
A1 Hiromasa Saitoh
A1 Aleksandra Białas
A1 Mark J Banfield
A1 Sophien Kamoun
A1 Ryohei Terauchi
YR 2017
UL http://biorxiv.org/content/early/2017/12/24/239400.abstract
AB A subset of plant nucleotide-binding domain and leucine-rich repeat-containing (NLR) proteins carry extraneous integrated domains that have been proposed to mediate pathogen effector recognition. The current view is that these unconventional domains function by directly binding or serving as substrates for pathogen effectors, yet only a few domains have been functionally characterized to date. Here we report that the integrated NOI domain of the rice NLR protein Pii-2, together with its partner Pii-1, mediates immunity to the rice blast fungus Magnaporthe oryzae by indirect recognition of the AVR-Pii effector. We discovered that the Pii-2 NOI domain does not physically interact with the effector itself but instead binds the host protein OsExo70-F3, which is a target of AVR-Pii. We further identified mutations within the NOI core motif (PxFGxW) of Pii-2 that abolish both OsExo70-F3 binding and Pii-mediated resistance to M. oryzae expressing AVR-Pii. This led us to propose a novel conceptual model in which an NLR-integrated domain functions to detect host proteins targeted by pathogen effectors, in a framework that extends classical indirect recognition models.