Penicillium expansum is a formidable postharvest pathogen responsible for significant economic losses in the fruit industry, affecting apples, pears, and other perishable crops. Beyond causing fruit decay, it produces patulin, a mycotoxin with serious food safety implications. While previous research has explored gene expression patterns, the role of chromatin structure and transcription factors in regulating fungal growth and infection has remained largely uncharted territory. Addressing these knowledge gaps is critical for developing effective disease control strategies.
In a study (DOI: 10.1093/hr/uhae264) published on September 20, 2024, in Horticulture Research, a research team from Jiangsu University leveraged ATAC-seq technology to profile chromatin accessibility in P. expansum during its vegetative growth and infection phases. Their analysis led to the identification of PeAtf1, a transcription factor that orchestrates fungal growth, reproduction, and stress adaptation. The study provides a pioneering view into how chromatin architecture influences gene regulation in this pathogen.
By utilizing ATAC-seq, the researchers mapped chromatin accessibility dynamics and uncovered six footprint-supported motifs linked to active transcription factors. They found that PeAtf1 plays a dual role—promoting vegetative growth and reproduction while suppressing the fungus's ability to tolerate oxidative, cell wall, and membrane stresses. Unexpectedly, deleting PeAtf1 did not impair P. expansum's pathogenicity in apple fruits, suggesting the presence of compensatory regulatory pathways. Interestingly, genes involved in oxidative stress response were upregulated in PeAtf1-deficient strains, potentially bolstering the fungus’s defense against host immune responses. These findings unveil intricate regulatory networks that dictate fungal adaptation and survival strategies.
“This study marks a significant step forward in understanding how chromatin accessibility and transcription factors like PeAtf1 shape fungal growth and stress resilience,” said Dr. Hongyin Zhang, the corresponding author. “By targeting these regulatory mechanisms, we can explore new approaches to combat postharvest fungal pathogens.”
The discoveries from this research hold far-reaching implications for agriculture and food safety. A deeper understanding of P. expansum's regulatory mechanisms paves the way for precision-targeted interventions, from novel fungicides to genetic modifications that disrupt fungal survival and infection. Moreover, the study’s integrative approach—combining ATAC-seq with functional transcription factor analysis—sets a new benchmark for future research on plant pathogens, potentially inspiring innovative solutions for disease management across various crops.
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References
DOI
10.1093/hr/uhae264
Original Source URL
https://doi.org/10.1093/hr/uhae264
Funding information
This work was supported by the National Natural Science Foundation of China (32072276; 32102030) and the China Postdoctoral Science Foundation (2023 M741440).
About Horticulture Research
Horticulture Research is an open access journal of Nanjing Agricultural University and ranked number one in the Horticulture category of the Journal Citation Reports ™ from Clarivate, 2023. The journal is committed to publishing original research articles, reviews, perspectives, comments, correspondence articles and letters to the editor related to all major horticultural plants and disciplines, including biotechnology, breeding, cellular and molecular biology, evolution, genetics, inter-species interactions, physiology, and the origination and domestication of crops.