Tremellafuciformis is one of higher basidiomycetes. Its basidiospore can reproduce yeast-like conidia, which is also called the blastospore by budding. The yeast-like conidia of T. fuciformis is monokaryotic and easy ...Tremellafuciformis is one of higher basidiomycetes. Its basidiospore can reproduce yeast-like conidia, which is also called the blastospore by budding. The yeast-like conidia of T. fuciformis is monokaryotic and easy to culture by submerged fermentation similar to yeast. Thus, it is a good recipient cell for exogenous gene expression. In this study, the expression plasmid pAN7-1 (containing promoter gpd-An derived from Aspergillus nidulans and selectable marker gene hph conferring resistance to hygromycin B) and plasmid pLg-hph (containing promoter gpd-Le derived from Lentinula edodes and selectable marker gene hph) were transformed into the yeast-like conidia of T. fuciformis by PEG-mediated protoplast transformation, respectively. The primary putative transformants were selected by the sandwich screening method with the selective medium containing 50 μg mL^-1 hygromycin. The putative transformants were obtained from the primary putative transformants transferred on PDSA plates containing 100 μg mL^-1 hygromycin for second round selection. Experimental results showed that the optimal concentration of PEG 4000 for mediating protoplast transformation was 25%. PCR and Southern blotting confirmed that the selectable marker gene hph was integrated effectively into the genome of the yeast-like conidia of T. fuciformis with plasmid pLg-hph transformation. Its transformation efficiency was 110 transformants per μg DNA, and the hph gene was integrated into the genome of some yeast-like conidia with plasmid pAN7-1 transformation. However, its transformation efficiency was only 9 transformants per μg DNA. The presence of hph gene in the genome of transformants after 5 generations of sub- culturing on PDSB medium was confirmed by PCR, suggesting that the foreign gene hph was stable during subculture.展开更多
[Objectives] This study was conducted to investigate the function of Dunaliella salina calmodulin kinase(CaM K) gene.[Methods] The sense and antisense gene fragments(223 bp) and spacer sequence(129 bp) of D.salina cal...[Objectives] This study was conducted to investigate the function of Dunaliella salina calmodulin kinase(CaM K) gene.[Methods] The sense and antisense gene fragments(223 bp) and spacer sequence(129 bp) of D.salina calmodulin kinase gene were cloned and inserted into the downstream part of the35 S promoter of the eukaryotic expression vector pM DCMGN-Cat.The siRNA expression system of CaM K gene was successfully constructed.The p CaM K-RNAi expression vector was transformed into D.salina cells by the LiA c/PEG-mediated method,giving transgenic D.salina.The expression of CaM K gene was then analyzed by real-time fluorescence quantitative PCR.[Results]The expression of CaM K gene in the transgenic D.salina was significantly reduced,by 70% compared with the control group,suggesting that the expression of CaM K gene was significantly inhibited.The examination of the growth status of D.salina showed that D.salina cell division and proliferation were also affected.It is proved that CaM K gene has a positive regulation effect on the division and proliferation of D.salina cells.[Conclusions] The study provides important information for further elucidating the function and action mechanism of D.salina calmodulin kinase gene.展开更多
基金funded by the National Hi-Tech Research and Development Program of China (863 Program,2006AA10Z301)the National Natural Science Foundation of China (30371000, 30671457)
文摘Tremellafuciformis is one of higher basidiomycetes. Its basidiospore can reproduce yeast-like conidia, which is also called the blastospore by budding. The yeast-like conidia of T. fuciformis is monokaryotic and easy to culture by submerged fermentation similar to yeast. Thus, it is a good recipient cell for exogenous gene expression. In this study, the expression plasmid pAN7-1 (containing promoter gpd-An derived from Aspergillus nidulans and selectable marker gene hph conferring resistance to hygromycin B) and plasmid pLg-hph (containing promoter gpd-Le derived from Lentinula edodes and selectable marker gene hph) were transformed into the yeast-like conidia of T. fuciformis by PEG-mediated protoplast transformation, respectively. The primary putative transformants were selected by the sandwich screening method with the selective medium containing 50 μg mL^-1 hygromycin. The putative transformants were obtained from the primary putative transformants transferred on PDSA plates containing 100 μg mL^-1 hygromycin for second round selection. Experimental results showed that the optimal concentration of PEG 4000 for mediating protoplast transformation was 25%. PCR and Southern blotting confirmed that the selectable marker gene hph was integrated effectively into the genome of the yeast-like conidia of T. fuciformis with plasmid pLg-hph transformation. Its transformation efficiency was 110 transformants per μg DNA, and the hph gene was integrated into the genome of some yeast-like conidia with plasmid pAN7-1 transformation. However, its transformation efficiency was only 9 transformants per μg DNA. The presence of hph gene in the genome of transformants after 5 generations of sub- culturing on PDSB medium was confirmed by PCR, suggesting that the foreign gene hph was stable during subculture.
基金Supported by National Natural Science Foundation of China(31472260,30972240)。
文摘[Objectives] This study was conducted to investigate the function of Dunaliella salina calmodulin kinase(CaM K) gene.[Methods] The sense and antisense gene fragments(223 bp) and spacer sequence(129 bp) of D.salina calmodulin kinase gene were cloned and inserted into the downstream part of the35 S promoter of the eukaryotic expression vector pM DCMGN-Cat.The siRNA expression system of CaM K gene was successfully constructed.The p CaM K-RNAi expression vector was transformed into D.salina cells by the LiA c/PEG-mediated method,giving transgenic D.salina.The expression of CaM K gene was then analyzed by real-time fluorescence quantitative PCR.[Results]The expression of CaM K gene in the transgenic D.salina was significantly reduced,by 70% compared with the control group,suggesting that the expression of CaM K gene was significantly inhibited.The examination of the growth status of D.salina showed that D.salina cell division and proliferation were also affected.It is proved that CaM K gene has a positive regulation effect on the division and proliferation of D.salina cells.[Conclusions] The study provides important information for further elucidating the function and action mechanism of D.salina calmodulin kinase gene.