Breeding a new strain with increased contents of individual ganoderic acids by mono-mono crossing of genetically modified monokaryons.

Ganoderic acids (GAs) are major functional components of . The study aimed to breed a new strain with increased contents of individual GAs. Two mating-compatible monokaryotic strains, G. 260125 and G. 260124, were successfully isolated from the dikaryotic CGMCC 5.0026 via protoplast formation and regeneration. The hemoglobin gene () and squalene synthase gene () were overexpressed in the monokaryotic G. 260124 and G. 260125 strain, respectively. Mating between the G. 260124 strain overexpressing and the G. 260125 strain overexpressing sqs resulted in the formation of the new hybrid dikaryotic strain sqs-vgb. The maximum contents of ganoderic acid (GA)-T, GA-Me, and GA-P in the fruiting body of the mated sqs-vgb strain were 23.1, 15.3, and 39.8 μg/g dry weight (DW), respectively, 2.23-, 1.75-, and 2.69-fold greater than those in 5.0026. The squalene and lanosterol contents increased 2.35- and 1.75-fold, respectively, in the fruiting body of the mated sqs-vgb strain compared with those in the 5.0026. In addition, the maximum expression levels of the and lanosterol synthase gene () were increased 3.23- and 2.13-fold, respectively, in the mated sqs-vgb strain. In summary, we developed a new strain with higher contents of individual GAs in the fruiting body by integrating genetic engineering and mono-mono crossing.