Explant browning is one of the major problems in the tissue culture process, and polyphenol oxidase(PPO), is the major proteases involved in plant tissue browning. We investigated the effects of polyphenol oxidase on ...Explant browning is one of the major problems in the tissue culture process, and polyphenol oxidase(PPO), is the major proteases involved in plant tissue browning. We investigated the effects of polyphenol oxidase on the early stage of browning in explants of the orchid Phalaenopsis. Our results show that PPO activity was significantly higher in explants cultured for 3 d than in the 0 h control. The levels of PPO transcripts and PPO protein were significantly higher in explants cultured for 6 h compared to the 0 h control; these high expression levels were maintained over increasing cultivation time. Cycloheximide(CHX) treatment reduced PPO transcript levels, PPO protein levels, and PPO enzyme activity. High levels of PPO m RNA and PPO protein were detected in the cytoplasm and vascular bundles of Phalaenopsis explants cultured for 6 h compared to explants cultured for 0 h, 24 h, and 3 d. CHX treatment did not significantly affect the distribution of PPO m RNA and PPO protein in explant tissues, but their levels were significantly lower than those of the untreated control.展开更多
香蕉在进行遗传转化过程中,外植体容易褐化,从而降低了再生频率,影响到遗传转化的效率。为降低香蕉转化过程中外植体的褐化率,采用香蕉(Musa AAA group cv.Brazilian)未成熟雄花作为外植体,以农杆菌介导法进行遗传转化。结果表明,当改良...香蕉在进行遗传转化过程中,外植体容易褐化,从而降低了再生频率,影响到遗传转化的效率。为降低香蕉转化过程中外植体的褐化率,采用香蕉(Musa AAA group cv.Brazilian)未成熟雄花作为外植体,以农杆菌介导法进行遗传转化。结果表明,当改良的MS培养基中铵态氮与硝态氮(NH4+/NO3-)的摩尔比为20.6:67.6时,具有较强的抗褐化能力。当6-BA浓度为1.0mg/L时,外植体易于诱导出胚状体。展开更多
基金supported by Natural Science Foundation in China(31070618)
文摘Explant browning is one of the major problems in the tissue culture process, and polyphenol oxidase(PPO), is the major proteases involved in plant tissue browning. We investigated the effects of polyphenol oxidase on the early stage of browning in explants of the orchid Phalaenopsis. Our results show that PPO activity was significantly higher in explants cultured for 3 d than in the 0 h control. The levels of PPO transcripts and PPO protein were significantly higher in explants cultured for 6 h compared to the 0 h control; these high expression levels were maintained over increasing cultivation time. Cycloheximide(CHX) treatment reduced PPO transcript levels, PPO protein levels, and PPO enzyme activity. High levels of PPO m RNA and PPO protein were detected in the cytoplasm and vascular bundles of Phalaenopsis explants cultured for 6 h compared to explants cultured for 0 h, 24 h, and 3 d. CHX treatment did not significantly affect the distribution of PPO m RNA and PPO protein in explant tissues, but their levels were significantly lower than those of the untreated control.
文摘香蕉在进行遗传转化过程中,外植体容易褐化,从而降低了再生频率,影响到遗传转化的效率。为降低香蕉转化过程中外植体的褐化率,采用香蕉(Musa AAA group cv.Brazilian)未成熟雄花作为外植体,以农杆菌介导法进行遗传转化。结果表明,当改良的MS培养基中铵态氮与硝态氮(NH4+/NO3-)的摩尔比为20.6:67.6时,具有较强的抗褐化能力。当6-BA浓度为1.0mg/L时,外植体易于诱导出胚状体。
