RESUMEN
Genetic engineering is a powerful tool in Panax ginseng breeding.Genetic transformation and plant regeneration are the premise and foundation involved in genetic engineering of Panax ginseng.Ginseng can be regenerated through organogenesis or somatic embryogenesis and indirect somatic embryogenesis is mainly used for its regeneration.Summurized the factors influencing plant regeneration such as different explants,different carbohydrates,somatic embryo optimization and hormone-free approach.Ginseng transformation has been achieved by Agrobacterium tumefaciens and Agrobacterium rhizogenes and transgenic ginseng with good characters was obtained by introducing genes associated with biosynthesis of ginsenosides or herbicide gene.Hairy root culture system can supply large scale of ginsenosides,thus effect of rolC genes on ginseng hairy root induction,regeneration and bioreactor culture of hairy root were discussed.Additionally,problems that are present in genetic engineering of Panax ginseng were also discussed in this review.
RESUMEN
RT-PCR amplification of ginseng ?-amyrin synthase gene was successfully performed based on the total RNAs extracted from ginseng hairy roots induced by Agrobacterium rhizogenes A4 using a modified guanidine isothiocyanate-method. Sequence analysis of this gene revealed that its sequence was consistent with the sequence of a previously reported ginseng ?-amyrin synthase gene (GenBank No. AB009030). This gene was inserted into pMD-119T simple vector and transformed into E.coli DH5?. Furthermore antisense plant expression vector of this gene was constructed using the pBI121 vector, laying foundation for studies on antisense regulation of ginseng ?-amyrin synthase gene.