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  • Use of the Puccinia sorghi haustorial transcriptome to identify and characterize AvrRp1-D recognized by the maize Rp1-D resistance protein
Title: Use of the Puccinia sorghi haustorial transcriptome to identify and characterize AvrRp1-D recognized by the maize Rp1-D resistance protein
The common rust disease of maize is caused by the obligate biotrophic fungusPuccinia sorghi. The maizeRp1-Dallele imparts resistance against theP.sorghiIN2 isolate by initiating a defense response that includes a rapid localized programmed cell death process, the hypersensitive response (HR). In this study, to identify AvrRp1-D fromP.sorghiIN2, we employed the isolation of haustoria, facilitated by a biotin-streptavidin interaction, as a powerful approach. This method proves particularly advantageous in cases where the genome information for the fungal pathogen is unavailable, enhancing our ability to explore and understand the molecular interactions between maize andP.sorghi. The haustorial transcriptome generated through this technique, in combination with bioinformatic analyses such as SignalP and TMHMM, enabled the identification of 251 candidate effectors. We ultimately identified two closely related genes,AvrRp1-D.1andAvrRp1-D.2, which triggered anRp1-D-dependent defense response inNicotiana benthamiana.AvrRp1-D-inducedRp1-D-dependent HR was further confirmed in maize protoplasts. We demonstrated that AvrRp1-D.1 interacts directly and specifically with the leucine-rich repeat (LRR) domain of Rp1-D through yeast two-hybrid assay. We also provide evidence that, in the absence of Rp1-D, AvrRp1-D.1 plays a role in suppressing the plant immune response. Our research provides valuable insights into the molecular interactions driving resistance against common rust in maize.  more » « less
Award ID(s):
2126256
PAR ID:
10555761
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; « less
Editor(s):
Schornack, Sebastian
Publisher / Repository:
PLOS Pathogens
Date Published:
Journal Name:
PLOS Pathogens
Volume:
20
Issue:
11
ISSN:
1553-7374
Page Range / eLocation ID:
e1012662
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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