SR5AL serves as a key regulatory gene in lycopene biosynthesis by Blakeslea trispora

BACKGROUND: Trisporic acids are considered to be key regulators of carotenoid biosynthesis and sexual reproduction in zygomycetes, but the mechanisms underlying this regulation have not been fully elucidated. RESULTS: In this study, the relationships between trisporic acids and lycopene synthesis were investigated in Blakeslea trispora. The lycopene concentration in single fermentation by the (−) strain with the addition of 24 μg/L trisporic acids was slightly higher than that observed in mated fermentation. After transcriptomic analysis, a steroid 5α-reductase-like gene, known as SR5AL in B. trispora, was first reported. 5α-Reductase inhibitors reduced lycopene biosynthesis and downregulated the expression of sex determination and carotenoid biosynthesis genes. Overexpression of the SR5AL gene upregulated these genes, regardless of whether trisporic acids were added. CONCLUSION: These findings indicated that the SR5AL gene is a key gene associated with the response to trisporic acids. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12934-022-01853-x.