The expression of β-D-glucuronidase(Gus)gene under the control of soybean heat shock protein (HSP)promoter Gmhsp17. 5-C was investigated in transgenic Nicotiana plumbaginifolia plants after heat shock treatment. Resu...The expression of β-D-glucuronidase(Gus)gene under the control of soybean heat shock protein (HSP)promoter Gmhsp17. 5-C was investigated in transgenic Nicotiana plumbaginifolia plants after heat shock treatment. Results of histochemical stain assay showed that the Gus activity increased markedly during the recovery phase(21℃)after heat shock treatment at 42℃ for 2 h. Results of quantitative fluorometric assays indicated that maximal Gus activity after heat shock treatment could reach 5-6 times higher than that before heat shock treatment in transgenic lines HG6 and HG9. Based on several advantages of the heat shock promoter such as easy to induce, sensitivity to heat shock and high inductive activity, it can be potentially used to control expression of gene of interest in transgenic plants.展开更多
: Using a degenerative probe designed according to the most conservative region of a known Lys- and His-specific amino acid transporter (LHT1) from Arabidopsis, we isolated a full-length cDNA named OxHT(histidine tran...: Using a degenerative probe designed according to the most conservative region of a known Lys- and His-specific amino acid transporter (LHT1) from Arabidopsis, we isolated a full-length cDNA named OxHT(histidine transporter of Oryza sativa L.) by screening the rice cDNA library. The cDNA is 1.3 kb in length and the open reading frame encodes for a 441 amino acid protein with a calculated molecular mass of 49 kDa. Multiple sequence alignments showed that OsHT shares a high degree of sequence conservation at the deduced amino acid level with the Arabidopsis LHT1 and six putative lysine and histidine transporters. Computational analysis indicated that OsHT is an integral membrane protein with 11 putative transmembrane helices. This was confirmed by the transient expression assay because the OsHT-GFP fusion protein was, indeed, localized mainly in the plasma membrane of onion epidermal cells. Functional complementation experiments demonstrated that OsHT was able to work as a histidine transporter in Saccharomyces cerevisiae, suggesting that OsHT is a gene that encodes for a histidine transporter from rice. This is the first time that an LHT-type amino acid transporter gene has been cloned from higher plants other than Arabidopsis.展开更多
基金supported by the National High Tech R&D Program of China(863 Program,2002AA2244011)the National Special Program for Research and Industrialization of Ttansgenic Plants,China(J2000-B-021).
文摘The expression of β-D-glucuronidase(Gus)gene under the control of soybean heat shock protein (HSP)promoter Gmhsp17. 5-C was investigated in transgenic Nicotiana plumbaginifolia plants after heat shock treatment. Results of histochemical stain assay showed that the Gus activity increased markedly during the recovery phase(21℃)after heat shock treatment at 42℃ for 2 h. Results of quantitative fluorometric assays indicated that maximal Gus activity after heat shock treatment could reach 5-6 times higher than that before heat shock treatment in transgenic lines HG6 and HG9. Based on several advantages of the heat shock promoter such as easy to induce, sensitivity to heat shock and high inductive activity, it can be potentially used to control expression of gene of interest in transgenic plants.
文摘: Using a degenerative probe designed according to the most conservative region of a known Lys- and His-specific amino acid transporter (LHT1) from Arabidopsis, we isolated a full-length cDNA named OxHT(histidine transporter of Oryza sativa L.) by screening the rice cDNA library. The cDNA is 1.3 kb in length and the open reading frame encodes for a 441 amino acid protein with a calculated molecular mass of 49 kDa. Multiple sequence alignments showed that OsHT shares a high degree of sequence conservation at the deduced amino acid level with the Arabidopsis LHT1 and six putative lysine and histidine transporters. Computational analysis indicated that OsHT is an integral membrane protein with 11 putative transmembrane helices. This was confirmed by the transient expression assay because the OsHT-GFP fusion protein was, indeed, localized mainly in the plasma membrane of onion epidermal cells. Functional complementation experiments demonstrated that OsHT was able to work as a histidine transporter in Saccharomyces cerevisiae, suggesting that OsHT is a gene that encodes for a histidine transporter from rice. This is the first time that an LHT-type amino acid transporter gene has been cloned from higher plants other than Arabidopsis.
