cry3A和vhb基因在转基因马铃薯中的表达

Expression of cry3A and vhb Genes in Transgenic Potato Plants

分别构建了含cry3A和cry3A +vhb基因的植物表达载体 pBCry3A和pBC3 Vhb,并通过根癌农杆菌介导转化了马铃薯 .对转化再生植株进行PCR和DNA印迹分析表明 ,外源基因已整合到马铃薯基因组中 ,且连续三代无性繁殖后转基因仍存在 .ELISA分析表明cry3A基因在转基因植株中得到了高效表达 ,在单转cry3A植株中最高表达量达0 1% ,转cry3A与vhb双基因株系中为 0 0 6 5 % .水涝试验显示 ,转双基因且vhbmRNA的RT PCR呈阳性的马铃薯植株 ,对低氧胁迫有较好的耐受性 。

Plant expression vectors, pBCry3A and pBC(3)Vhb, containing cry3A gene and both cry3A and vhb genes respectively, were constructed. Potato leaf-explants were transformed via Agrobacterium harboring pBCry3A or pBC3Vhb respectively. Results from PCR and genomic DNA Southern blotting analysis indicate that cry3A or cry3A + vhb gene have been integrated into the genome of the transformed potato lines with 1 similar to 3 copies at least for cry3A gene. The transgenes were stable and expressed even after three successive clonic propagations. Results from ELISA analysis showed that the highest expression level of Cry3A protein reached 0. 1 % of total leaf soluble protein among cry3A transgenic plants, while that of the cry3A + vhb transgenic plant reached 0. 065 %. RT-PCR analysis of vhb mRNA and waterlogging test demonstrated that the transgenic potato plants transformed with cry3A + vhb genes expressed vhb gene at least at transcription level and showed obvious higher tolerance against low-oxygen stress. These results together with that of the ELISA for Cry3A indicate that this kind of transgenic plants could be valuble in application for insect resistance and waterlogging tolerance.