Method of increasing content of tanshinone in hairy roots of salvia miltiorrhiza bunge through cotransformation of SmHMGR and SmDXR double genes

The invention relates to the field of biological technology and discloses a method of increasing the content of tanshinone. According to the method, the 3-hydroxy-3-methylglutaryl coenzyme A reductase gene SmHMGR and the 1-deoxy-D-xylosone-5-phosphate reductase gene SmDXR of salvia miltiorrhiza bunge are used to construct a recombinant vector, and genetic transformation is carried out on leaves of salvia miltiorrhiza bunge so as to obtain hairy roots of salvia miltiorrhiza bunge with transgenic SmHMGR and SmDXR genes. The content of tanshinone in the obtained transgenic hairy roots of salvia miltiorrhiza bunge in the invention substantially increases, and total tanshinone content in a line (HD34) of cotransformed SmHMGR and SmDXR double genes is 5.30 times of that of a comparison hairy root of salvia miltiorrhiza bunge. The invention provides the method for increasing content of tanshinone in the hairy roots of salvia miltiorrhiza bunge, providing a novel high-quality drug source for producing tanshinone in critical clinical demand and having a positive promotion effect in alleviating shortage of drug sources for tanshinone.