摘要
Genomic research has made a large number of sequences of novel genes orexpressed sequence tags available. To investigate functions of these genes, a system for conditionalcontrol of gene expression would be a useful tool. Inducible trans-gene expression that uses greenfluorescent protein gene (gfp) as a reporter gene has been investigated in transgenic cell lines ofcotton (COT; Gossypium hirsutum L.), Fraser fir [FRA; Abies fraseri (Pursh) Poir], Nordmann fir(NOR; Abies nord-manniana Lk.), and rice (RIC; Oryza sativa L. cv. Radon). Transgenic cell lineswere used to test the function of the chemical inducer dexamethasone. Inducible transgene expressionwas observed with fluorescence and confocal microscopy, and was confirmed by northern blotanalyses. Dexamethasone at 5 mg/L induced gfp expression to the nearly highest level 48 h aftertreatment in COT, FRA, NOR, and RIC. Dexamethasone at 10 mg/L inhibited the growth of transgeniccells in FRA and NOR, but not COT and RIC. These results demonstrated that concentrations of inducerfor optimum inducible gene expression system varied among transgenic cell lines. The inducible geneexpression system described here was very effective and could be valuable in evaluating thefunction of novel gene.
Genomic research has made a large number of sequences of novel genes orexpressed sequence tags available. To investigate functions of these genes, a system for conditionalcontrol of gene expression would be a useful tool. Inducible trans-gene expression that uses greenfluorescent protein gene (gfp) as a reporter gene has been investigated in transgenic cell lines ofcotton (COT; Gossypium hirsutum L.), Fraser fir [FRA; Abies fraseri (Pursh) Poir], Nordmann fir(NOR; Abies nord-manniana Lk.), and rice (RIC; Oryza sativa L. cv. Radon). Transgenic cell lineswere used to test the function of the chemical inducer dexamethasone. Inducible transgene expressionwas observed with fluorescence and confocal microscopy, and was confirmed by northern blotanalyses. Dexamethasone at 5 mg/L induced gfp expression to the nearly highest level 48 h aftertreatment in COT, FRA, NOR, and RIC. Dexamethasone at 10 mg/L inhibited the growth of transgeniccells in FRA and NOR, but not COT and RIC. These results demonstrated that concentrations of inducerfor optimum inducible gene expression system varied among transgenic cell lines. The inducible geneexpression system described here was very effective and could be valuable in evaluating thefunction of novel gene.