INTRODUCTION OF β-GLUCURONIDASE GENE INTO GINSENG (PANAX CINSENG) BY A TI-PLASMID VECTOR SYSTEM AND ITS EXPRESSION
β-Glucuronidase (GUS) gene of Escherichia coli was introduced into ginseng cells by an Agrobacterium binary vector system and expressed in somatic embryos derived from the cells. A binary vector pBI121 carrying CaMV 35S promoter-GUS gene fusion and a neomycin phosphotransferase gene as selection marker was transferred into Agrobacterium tumefaciens LBA4404. Zygotic embryo cotyledonary segments were co-cultivated with A. tumefaciens and transferred to the medium containg 1 mg 2,4-dichlorophenoxyacetic acid/liter, 0.5 mg kinetin/liter, and 100 mg kanamycin/liter. Kanamycin-resistant calli were formed after 3 to 4 weeks of culture. Southern analysis confirmed the resistant calli were transformed with GUS gene. High GUS activities were detected in somatic embryos developed from the calli.