The fungal metabolite 4‐hydroxyphenylacetic acid from Neofusicoccum parvum modulates defence responses in grapevine

Abstract

In a consequence of global warming, grapevine trunk diseases (GTDs) have become a pertinent problem to viticulture, because endophytic fungi can turn necrotrophic upon host stress killing the plant. In Neofusicoccum parvum Bt‐67, plant‐derived ferulic acid makes the fungus release Fusicoccin aglycone triggering plant cell death. Now, we show that the absence of ferulic acid lets the fungus secrete 4‐hydroxyphenylacetic acid (4‐HPA), mimicking the effect of auxins on grapevine defence and facilitating fungal spread. Using Vitis suspension cells, we dissected the mode of action of 4‐HPA during defence triggered by the bacterial cell‐death elicitor, harpin. Early responses (cytoskeletal remodelling and calcium influx) are inhibited, as well as the expression of Stilbene Synthase 27 and phytoalexin accumulation. In contrast to other auxins, 4‐HPA quells transcripts for the auxin conjugating GRETCHEN HAGEN 3. We suggest that 4‐HPA is a key component of the endophytic phase of N. parvum Bt‐67 preventing host cell death. Therefore, our study paves the way to understand how GTDs regulate their latent phase for successful colonisation, before turning necrotrophic and killing the vines.

Marine-Fungus-Derived Natural Compound 4-Hydroxyphenylacetic Acid Induces Autophagy to Exert Antithrombotic Effects in Zebrafish

“…HPA is a phenolic compound that was first isolated from the pathogen Hypochnus sasakii [26] and subsequently found in the fungi Oidiodendron sp. [27] and Neofusicoccum parvum [28], the brown alga Undaria [29], colonic microorganisms [30], the Chinese herb Aster tataricus [31], and human saliva [32]. This compound has a wide range of effects, such as attenuating sepsis-induced acute kidney injury [30], preventing acute acetaminophen-induced liver injury [33], reducing inflammation and edema in lung injury [31], and regulating growth [29,34], anxiolytic [35], antioxidative [36], antimicrobial [37,38], and nematicidal activity [27].…”