Functional Divergence of Two Secreted Immune Proteases of Tomato

Rcr3 and Pip1 are paralogous secreted papain-like proteases of tomato. Both proteases are inhibited by Avr2 from the fungal pathogen Cladosporium fulvum, but only Rcr3 acts as a co-receptor for Avr2 recognition by the tomato Cf-2 immune receptor [ 1, 2, 3 and 4]. Here, we show that Pip1-depleted tomato plants are hyper-susceptible to fungal, bacterial, and oomycete plant pathogens, demonstrating that Pip1 is an important broad-range immune protease. By contrast, in the absence of Cf-2, Rcr3 depletion does not affect fungal and bacterial infection levels but causes increased susceptibility only to the oomycete pathogen Phytophthora infestans. Rcr3 and Pip1 reside on a genetic locus that evolved over 36 million years ago. These proteins differ in surface-exposed residues outside the substrate-binding groove, and Pip1 is 5- to 10-fold more abundant than Rcr3. We propose a model in which Rcr3 and Pip1 diverged functionally upon gene duplication, possibly driven by an arms race with pathogen-derived inhibitors or by coevolution with the Cf-2 immune receptor detecting inhibitors of Rcr3, but not of Pip1.

Bibliographic Details

Main Authors:	Ilyas, M., Hörger, A.C., Bozkurt, T.O., van den Burg, H.A., Kaschani, F., Kaiser, M., Belhaj, K., Smoker, M., Joosten, M., Kamoun, S., van der Hoorn, R.A.L.
Format:	Article/Letter to editor biblioteca
Language:	English
Subjects:	cf-2-dependent disease resistance, defense, gene, genome sequence, pathogen effectors, plant-pathogens, provides insights, specialization, target, transcription factors,
Online Access:	https://research.wur.nl/en/publications/functional-divergence-of-two-secreted-immune-proteases-of-tomato
Tags:	Add Tag No Tags, Be the first to tag this record!