The compound disrupts the process of autophagy, a process that maintains homeostasis, in fungi
By ARYAMAN BHATIA — science@theaggie.org
Researchers at UC Davis have published a study identifying a potent new fungicide that could revolutionize crop protection. Named ebselen, the chemical has shown remarkable efficacy in combating fungal infections in various crops. Additionally, it has demonstrated the ability to alleviate pre-existing fungal infections in rice.
Fungal pathogens wreak havoc on global crop yields.
“Annual crop losses are estimated to be USD 550 billion worldwide,” the study reads. “About 40% of the total crop loss is due to plant diseases of which loss by fungal pathogens is about USD 150 billion.”
In the study, which was published in Nature Communications, UC Davis researchers explain how they targeted autophagy, a vital cellular recycling process crucial for fungal pathogenicity.
“We discovered that macroautophagy plays an important role in delimiting the PCD [programmed cell death] to the infection site,” the lab website reads. “Autophagy is a dynamic process conserved across eukaryotes that entails the engulfment of cellular components in double membrane vesicles called autophagosomes that are then targeted to the vacuole/lysosome for degradation or recycling.”
According to senior author Savithramma Dinesh-Kumar, a professor of plant biology, ebselen’s efficacy lies in its ability to disrupt fungal autophagy, offering valuable insights into the development of next-generation antifungal compounds.
Using an innovative screening method based on bioluminescence, the researchers identified 30 chemicals capable of inhibiting a key enzymatic step in fungal autophagy. Among these, ebselen emerged as the most promising candidate, outperforming existing fungicides in preventing fungal growth.
By targeting this process, researchers believe they can significantly reduce fungal pathogenicity. Petri dish experiments revealed ebselen’s ability to inhibit fungal germination and growth, protecting various plant species from infection. Moreover, it showed promise in treating existing fungal infections in rice plants.
While initial tests suggest ebselen specificity in inhibiting fungal autophagy, further research is needed to assess its safety and potential cross-reactivity. The UC Davis team plans to expand their screening efforts to identify additional autophagy modulators with broader applications.
“Since autophagy is highly conserved across different organisms, including humans, more work needs to be done to test the cross-reactivity of the drug,” Dinesh-Kumar said during an interview with the UC Davis College of Biological Sciences.
The team now plans to test a larger variety of chemicals to see if they produce similar effects.
“The chemical space is very large, and some chemical libraries have more than 50,000 compounds,” Dinesh-Kumar said. “The next step will be to screen for additional autophagy modulators that might help control not just plant fungal pathogens, but also human fungal pathogens.”
Written by: Aryaman Bhatia — science@theaggie.org
