MYCOLab Ai Logo - gold and army green

Circadian clock is critical for fungal pathogenesis by regulating zinc starvation response and secondary metabolism

Summary

Scientists discovered that Fusarium oxysporum, a fungus that causes plant diseases, uses an internal clock system to time its attacks on plants. The fungus is most dangerous at dawn, when it activates special genes to survive the plant’s defenses and produce toxins. By disrupting the fungus’s clock genes, researchers found they could make it harmless. This discovery could lead to new ways to protect crops by targeting the pathogen’s timing system rather than using traditional fungicides.

Background

Circadian clocks regulate biological processes in organisms from bacteria to humans, but their role in fungal pathogen virulence remains poorly understood. Fusarium oxysporum is a major plant pathogen that causes diseases in multiple crops. This study investigates whether the circadian clock system influences F. oxysporum’s pathogenicity.

Objective

To determine the role of circadian clock genes in regulating Fusarium oxysporum pathogenesis and identify the molecular mechanisms controlling fungal virulence. The researchers examined how clock-controlled transcription factors regulate zinc starvation responses and secondary metabolite production.

Results

F. oxysporum possesses a functional circadian clock with FoFRQ1 and FoFRH as core negative regulators and FoWC1-FoWC2 as positive regulators. Disruption of clock genes dramatically reduced fungal pathogenicity. The circadian clock regulated rhythmic expression of transcription factors FoZafA and FoCzf1, which control zinc starvation adaptation and fusaric acid production, respectively. Pathogenicity exhibited diurnal variation, peaking at dawn (Pathogen-ZT0).

Conclusion

The circadian clock is critical for F. oxysporum virulence by orchestrating temporal control of stress responses and secondary metabolism. Clock-controlled transcription factors enable the pathogen to adapt to zinc starvation and produce phytotoxins, representing sophisticated mechanisms for optimal host invasion timing. These findings suggest circadian clock-based strategies could be developed for managing soilborne pathogens.
  • Published in:Science Advances,
  • Study Type:Experimental Research Study,
  • Source: PMID: 40153515, DOI: 10.1126/sciadv.ads1341
Scroll to Top