The purpose of this study is to investigate the function of a novel potassium transporter gene (NrHAK1) isolated from Nicotiana rustica roots using yeast complement and real-time PCR technique. The complementary DNA (...The purpose of this study is to investigate the function of a novel potassium transporter gene (NrHAK1) isolated from Nicotiana rustica roots using yeast complement and real-time PCR technique. The complementary DNA (cDNA) of NrHAK1, 2 488 bp long, contains an open reading frame (ORF) of 2 334 bp encoding a protein of 777 amino acids (87.6 kDa) with 12 predicted transmembrane domains. The NrHAK1 protein shows a high sequence similarity to those of high-affinity potassium transporters in Mesembryanthemum, Phytolacca acinosa, Arabidopsis thaliana, and so on. We found that the NrHAK1 gene could complement the yeast-mutant defect in K+ uptake. Among several tissues surveyed, the expression level of NrHAK1 was most abundant in the root tip and was up-regulated when exposed to potassium starvation. Moreover, the transcript accumulation was significantly reduced by adding 5 mmol/L NH4+ to the solution. These results suggest that NrHAK1 plays an important role in potassium absorption in N. rustica.展开更多
Somatic embryo is widely used in genetic engineering and cell engineering. This paper reviewed the recent research results of somatic embryogenesis in Cucurbitaceae plants. Somatic embryogenesis is controlled by many ...Somatic embryo is widely used in genetic engineering and cell engineering. This paper reviewed the recent research results of somatic embryogenesis in Cucurbitaceae plants. Somatic embryogenesis is controlled by many factors such as genotype, explant type, seedling age, basal culture medium, carbohydrate, nitrogen, growth regulators, additives and illumination et al.. Abnormality, desynchrony and browning are the main problem existing in Cucurbitaceae somatic embryogenesis. Then some ideas on how to obtain high quality somatic embryo are given. At last, we forecast the application of somatic embryo in breeding of Cucurbitaceae plants.展开更多
基金(No. 110200101008) supported by the State Tobacco Mo-nopoly Administration, China
文摘The purpose of this study is to investigate the function of a novel potassium transporter gene (NrHAK1) isolated from Nicotiana rustica roots using yeast complement and real-time PCR technique. The complementary DNA (cDNA) of NrHAK1, 2 488 bp long, contains an open reading frame (ORF) of 2 334 bp encoding a protein of 777 amino acids (87.6 kDa) with 12 predicted transmembrane domains. The NrHAK1 protein shows a high sequence similarity to those of high-affinity potassium transporters in Mesembryanthemum, Phytolacca acinosa, Arabidopsis thaliana, and so on. We found that the NrHAK1 gene could complement the yeast-mutant defect in K+ uptake. Among several tissues surveyed, the expression level of NrHAK1 was most abundant in the root tip and was up-regulated when exposed to potassium starvation. Moreover, the transcript accumulation was significantly reduced by adding 5 mmol/L NH4+ to the solution. These results suggest that NrHAK1 plays an important role in potassium absorption in N. rustica.
文摘Somatic embryo is widely used in genetic engineering and cell engineering. This paper reviewed the recent research results of somatic embryogenesis in Cucurbitaceae plants. Somatic embryogenesis is controlled by many factors such as genotype, explant type, seedling age, basal culture medium, carbohydrate, nitrogen, growth regulators, additives and illumination et al.. Abnormality, desynchrony and browning are the main problem existing in Cucurbitaceae somatic embryogenesis. Then some ideas on how to obtain high quality somatic embryo are given. At last, we forecast the application of somatic embryo in breeding of Cucurbitaceae plants.