The b‐ZIP transcription factor FgTfmI is required for the fungicide phenamacril tolerance and pathogenecity in Fusarium graminearum

Abstract

BACKGROUND Fusarium head blight (FHB) is a devastating disease of cereal crops worldwide mainly caused by Fusarium graminearum. Due to the unavailability of FHB‐resistant wheat cultivars, chemical fungicide application is currently the most effective approach for controlling FHB now. In the last few years, a novel cyanoacrylate fungicide, phenamacril, has been widely used in China for FHB disease management. In previous studies, we identified that myosin I (FgMyo1) is the target of phenamacril and is essential for mycotoxin deoxynivalenol (DON) biosynthesis and fungal growth. However, the regulation of FgMYO1 gene expression is still largely unknown. RESULTS In this study, we identified a b‐ZIP transcription factor, FgTfmI, which regulates the mRNA expression of FgMYO1 upon phenamacril treatment. The FgTfmI directly binds to the promoter region of FgMYO1, and is required for the upregulation of FgMYO1 in response to phenamacril treatment. The deletion mutant of FgTFMI (ΔFgTfmI) displayed a slight growth defect, while it showed hypersensitivity to phenamacril, but not to other tested fungicides. FgTfmI also contributed to DON biosynthesis and the infection process in planta. CONCLUSIONS The transcription factor FgTfmI plays an important role in regulating transcription of the genes involved in phenamacril tolerance, DON biosynthesis and virulence in F. graminearum. © 2019 Society of Chemical Industry

Inhibition of Fusarium Graminearum Growth and Deoxynivalenol Biosynthesis by Phenolic Compounds

“…Due to the increasing severity and frequency of FHB epidemics, the contamination of DON has been becoming a challenging social problem [7] . Currently, chemical fungicides are the most effective measure for the control of FHB, the carbendazim and azole fungicides have been used commonly for decades [8] . Unfortunately, the decreased incidence of FHB associated with fungicides does not always correspond to mycotoxins levels.…”

“…[7] Currently, chemical fungicides are the most effective measure for the control of FHB, the carbendazim and azole fungicides have been used commonly for decades. [8] Unfortunately, the decreased incidence of FHB associated with fungicides does not always correspond to mycotoxins levels. Some studies have observed that carbendazim, [9] tebuconazole, [10] and azoxystrobin [11] can stimulate DON production.…”

Comparative transcriptome analysis reveals distinct gene expression profiles in Fusarium graminearum challenged with carbendazim and phenamacril

“…The deletion mutant of FgFim, encoding actin-binding protein Fimbrin in F. graminearum, exhibited highly resistant to phenamacril and reduced production of DON [11]. FgTfmI, a b-ZIP transcription factor identi ed in F. graminearum, regulates the mRNA expression of FgMYO1 in response to phenamacril treatment, and contributes to DON biosynthesis during the infection process [17]. Recently, Fu et al predicted 4 novel residues responsible for phenamacril binding with FgMyo1 and subsequently discovered a novel phenamacril derivative, which displayed better activity on conidial germination against phenamacril-resistant strains of F. graminearum and dramatically inhibited its DON biosynthesis [18].…”

Development of a versatile copper‐responsive gene expression system in the plant‐pathogenic fungus Fusarium graminearum

“…However, only one conditional gene expression system is currently available in F. graminearum. This system is based on the P ZEAR promoter, which is activated by zearalenone or the oestrogenic compound β-estradiol (Lee et al, 2010(Lee et al, , 2011a, and has been successfully applied to analyse the function of essential genes in this fungus (Bui et al, 2016;Lee et al, 2011b;Liu et al, 2019;Nguyen et al, 2020;Tang et al, 2018). The P ZEAR system has limitations in that it cannot be used in studies of zearalenone biosynthesis.…”