Genome Editing Technology and Its Application Potentials in the Industrial Filamentous Fungus Aspergillus oryzae

Aspergillus oryzae is a filamentous fungus that has been used in traditional Japanese brewing industries, such as the sake, soy sauce, and miso production. In addition, A. oryzae has been used in heterologous protein production, and the fungus has been recently used in biosynthetic research due to its ability to produce a large amount of heterologous natural products by introducing foreign biosynthetic genes. Genetic manipulation, which is important in the functional development of A. oryzae, has mostly been limited to the wild strain RIB40, a genome reference suitable for laboratory analysis. However, there are numerous industrial brewing strains of A. oryzae with various specialized characteristics, and they are used selectively according to the properties required for various purposes such as sake, soy sauce, and miso production. Since the early 2000s, genome editing technologies have been developed; among these technologies, transcription activator-like effector nucleases (TALENs) and clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) have been applied to gene modification in A. oryzae. Notably, the CRISPR/Cas9 system has dramatically improved the efficiency of gene modification in industrial strains of A. oryzae. In this review, the development of genome editing technology and its application potentials in A. oryzae are summarized.