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  • A single phosphorylatable amino acid residue is essential for the recognition of multiple potyviral HCPro effectors by potato Nytbr
Title: A single phosphorylatable amino acid residue is essential for the recognition of multiple potyviral HCPro effectors by potato Nytbr
Abstract Potato virus Y(PVY,Potyviridae) is among the most important viral pathogens of potato. The potato resistance geneNytbrconfers hypersensitive resistance to the ordinary strain of PVY (PVYO), but not the necrotic strain (PVYN). Here, we unveil that residue 247 of PVY helper component proteinase (HCPro) acts as a central player controllingNytbrstrain‐specific activation. We found that substituting the serine at 247 in the HCPro of PVYO(HCProO) with an alanine as in PVYNHCPro (HCProN) disruptsNytbrrecognition. Conversely, an HCProNmutant carrying a serine at position 247 triggers defence. Moreover, we demonstrate that plant defences are induced against HCProOmutants with a phosphomimetic or another phosphorylatable residue at 247, but not with a phosphoablative residue, suggesting that phosphorylation could modulateNytbrresistance. Extending beyond PVY, we establish that the same response elicited by the PVYOHCPro is also induced by HCPro proteins from other members of thePotyviridaefamily that have a serine at position 247, but not by those with an alanine. Together, our results provide further insights in the strain‐specific PVY resistance in potato and infer a broad‐spectrum detection mechanism of plant potyvirus effectors contingent on a single amino acid residue.  more » « less
Award ID(s):
2152260
PAR ID:
10609806
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
PubMed Central
Date Published:
Journal Name:
Molecular Plant Pathology
Volume:
25
Issue:
11
ISSN:
1464-6722
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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