Work

A single phosphorylatable amino acid residue is essential for the recognition of multiple potyviral HCPro effectors by potato Ny tbr

Year: 2024

Type: article

Abstract: Potato virus Y (PVY, Potyviridae ) is among the most important viral pathogens of potato. The potato resistance gene Ny tbr confers hypersensitive resistance to the ordinary strain of PVY (PVY O ), but not the necrotic strain (PVY N ). Here, we unveil that residue 247 of PVY helper component proteinase (HCPro) acts as a central player controlling Ny tbr strain‐specific activation. We found that substituting the serine at 247 in the HCPro of PVY O (HCPro O ) with an alanine as in PVY N HCPro (HCPro N ) disrupts Ny tbr recognition. Conversely, an HCPro N mutant carrying a serine at position 247 triggers defence. Moreover, we demonstrate that plant defences are induced against HCPro O mutants with a phosphomimetic or another phosphorylatable residue at 247, but not with a phosphoablative residue, suggesting that phosphorylation could modulate Ny tbr resistance. Extending beyond PVY, we establish that the same response elicited by the PVY O HCPro is also induced by HCPro proteins from other members of the Potyviridae family 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.

Source: Molecular Plant Pathology

DOI: 10.1111/mpp.70027