What does this research mean for the field?

ZmPHT3 enhances maize broad-spectrum disease resistance by promoting the accumulation of phenol amides and stabilizing the phloem protein ZmPP2-B8. Novelty: ClaimNovelty.NOVEL_FINDING. Consensus alignment: ConsensusAlignment.NEUTRAL.

What question did this study set out to answer?

The aim is to explore how ZmPHT3 regulates phenol amides and their role in maize disease resistance.

March 1, 2026

Phenol amide regulator ZmPHT3 targets phloem protein ZmPP2-B8 to enhance maize broad-spectrum disease resistance

Key Points

The aim is to explore how ZmPHT3 regulates phenol amides and their role in maize disease resistance.
Characterization of ZmPHT3 gene in maize through expression analysis during pathogen infection.
Assessment of fungal growth in response to ZmPHT3 overexpression and disruption.
Exogenous application of phenol amides to zmpht3 mutants to evaluate antimicrobial effects.
Investigating protein interactions between ZmPHT3 and ZmPP2-B8.
Analysis of lignin biosynthesis and cellulose synthase gene expression post-interaction.
Overexpression of ZmPHT3 increased phenol amide levels, enhancing resistance against fungal pathogens.
Disruption of ZmPHT3 led to decreased phenol amide levels and increased susceptibility to infection.
Exogenous application of Cou-put and Caf-put partially restored disease resistance in zmpht3 mutants.
ZmPHT3 proved to physically interact with ZmPP2-B8, confirming their synergistic roles in enhancing immunity.
Silencing ZmPP2-B8 impaired disease resistance and validated the cooperative mechanism of ZmPHT3 and ZmPP2-B8.

Abstract

Phenol amides (PAs), a class of plant secondary metabolites, play crucial roles in plant defense, yet the genes regulating their biosynthesis and functional mechanisms against pathogens in maize remain poorly characterized. Here, we demonstrated that pathogen infection upregulates ZmPHT3, which encodes a BAHD acyltransferase essential for driving the accumulation of p-coumaroylputrescine (Cou-put), N-caffeoylputrescine (Caf-put), and N-feruloylputrescine N-glucoside (Fer-put-glu). Overexpression of ZmPHT3 boosted the levels of these compounds, consequently suppressing hyphal growth and strengthening resistance. Conversely, disruption of ZmPHT3 diminished PA accumulation, leading to increased hyphal expansion and higher susceptibility. Exogenous application of Cou-put and Caf-put partially restored fungal growth restriction in zmpht3 mutants, confirming the antimicrobial function of PAs. Mechanistically, we found that ZmPHT3 modulates the phloem protein ZmPP2-B8 via two distinct pathways: direct protein interaction and through the action of its enzymatic products. This model is supported by multiple lines of evidence: ZmPHT3 physically interacted with ZmPP2-B8; a catalytically inactive ZmPHT3 variant failed to promote ZmPP2-B8 protein accumulation; and treatment with Caf-put, Cou-put, or Fer-put elevated ZmPP2-B8 protein levels. Silencing ZmPP2-B8 impaired disease resistance, and silencing both ZmPHT3 and ZmPP2-B8 demonstrated that their encoded proteins act synergistically to promote immunity. Furthermore, ZmPHT3 and ZmPP2-B8 cooperatively upregulated lignin biosynthesis and cellulose synthase genes, enhancing cell wall fortification. Our findings unveil a defense mechanism in which pathogen-induced ZmPHT3 promotes accumulation of PAs that function dually as antimicrobial agents and ZmPP2-B8 stabilizers, forming a synergistic module that reinforces the cell wall and broadens the resistance spectrum in maize.

KI fragen

Bookmark

Cite This Study

Gong et al. (Wed,) studied this question.

synapsesocial.com/papers/69a3d800ec16d51705d2e820 https://doi.org/https://doi.org/10.1093/plphys/kiag091

Also Consider

Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context:

KI fragen

Bookmark