In a new report published in GEN Biotechnology (the sister journal to GEN), researchers from Seoul National University (SNU) in South Korea have applied CRISPR gene editing to produce tomato fruits with enhanced levels of provitamin D3 (ProVitD3).
In humans, ProVitD3 is a precursor for the synthesis of biologically active vitamin D3 and serves as a protective agent against ultraviolet radiation on the skin. Circulatory vitamin D often falls below desirable levels, particularly among individuals with limited exposure to sunlight. While dietary supplements help address this deficiency, natural vitamin D sources are restricted to a few animal-derived sources, such as fish, egg yolks, and beef liver, as fruits and vegetables have historically shown limited capacity for ProVitD3 production.
In the new study—featured on the cover of the June issue of GEN Biotechnology—Sunghwa Choe, PhD, and his colleagues at SNU used CRISPR gene editing in tomatoes to induce a loss of function in one of two DWARF5 (DWF5) genes, a homologue of the human gene (DHCR7) responsible for converting ProVitD3 to cholesterol. The plant homologue of DHCR7 was initially identified in Arabidopsis thaliana as DWF5.
Given a high sequence identity of more than 83%, the Korean team hypothesized that the two tomato DWF5 genes, SIDWF5A and SIDWF5B, function redundantly in their biosynthetic pathways. They chose to edit SIDWF5A after spatial expression patterns showed that transcript levels of SIDWF5A were 2–5 times higher than those of SIDWF5B, especially in green and red fruits.
Read more at genengnews.com
