Genome editing for biodiesel production in oleaginous microalga, Nannochloropsis species

Abstract

Algae are oxygen-producing photosynthetic aquatic organisms. Algal biodiesels have attracted attention because these fuels are produced via photosynthesis, which assimilates CO₂. Algal biodiesels are sustainable, not competitive with food production, and have higher productivity compared with terrestrial plants. However, the production costs of algal biodiesels are much higher than those of fossil fuels. Therefore, improvement of algal lipid productivity is essential for the practical use of algal biodiesels. To achieve this, the application of genome-editing systems for the molecular breeding of algae is expected to generate “high-performance algae.” Here, we review the genome-editing technologies developed for the oleaginous microalgae, Nannochloropsis species, which are the most promising algae for producing algal-biodiesel feedstock. In this review, we discuss the development of genome-editing systems for gene disruption, transgene-free genome-editing systems, transcriptional regulation systems using nuclease-deficient Cas proteins, and the applications of genome editing in Nannochloropsis species.