# CRISPR-Cas9 Gene Editing in Aspergillus: From Pathogenesis to Metabolic Engineering

## TL;DR

This review discusses how CRISPR-Cas9 gene editing is transforming the study and use of Aspergillus fungi in both health and industry.

## Contribution

The paper provides a comprehensive overview of CRISPR-Cas9 applications in Aspergillus, focusing on pathogenesis and metabolic engineering.

## Key findings

- CRISPR-Cas9 enables precise genetic modifications in Aspergillus species for functional genomics.
- The system is used to reduce mycotoxin production and enhance industrial metabolite output.
- Future challenges include improving the safety and efficiency of CRISPR-Cas9 in fungal strains.

## Abstract

Aspergillus molds play dual roles in industry and as opportunistic pathogens. Understanding and optimizing their functions requires precise genome editing. The CRISPR–Cas9 system, adapted from bacterial immunity, has become a key tool for targeted genetic modification in Aspergillus. It enables research into disease mechanisms, reduction in mycotoxin production, and the engineering of strains for industrial applications such as enzyme and metabolite production. This review outlines the principles of CRISPR–Cas9, highlights its applications in Aspergillus species, and discusses future challenges in developing safer, more efficient fungal strains.

The genus Aspergillus comprises over 600 species of filamentous fungi. This genus significantly impacts human health, food fermentation, and industrial biotechnology. With the in-depth research and applications of Aspergillus species in many fields, the establishment of efficient gene editing technologies is crucial for functional genomics studies and cell factory development. The clustered regularly interspaced short palindromic repeats and associated protein (CRISPR-Cas9) system, as a newly developed and powerful genome editing tool, has demonstrated exceptional potential for precise genetic modifications in various Aspergillus species. The continuous advancement of CRISPR-Cas9 technology has enabled precise gene editing and modification in both pathogenic and industrial Aspergillus strains, thereby driving innovations in pathogenicity attenuation, metabolic engineering, and functional genomics. Therefore, this review provides a concise overview of the CRISPR-Cas9 system, detailing its composition, working mechanism, and key functional features such as the role of the Cas9 protein and the protospacer adjacent motifs (PAMs). Subsequently, we focus on the transformative applications of CRISPR-Cas9 in Aspergillus species, discussing its pivotal roles in elucidating pathogenic mechanisms, disrupting mycotoxin biosynthesis, and employing metabolic engineering to enhance the production of industrial enzymes, organic acids, and valuable natural products. Finally, we discuss future challenges and promising opportunities for applying CRISPR-Cas9 technology to advance the industrial biotechnology of Aspergillus species.