GhACT1启动子驱动Lc基因在棉花幼胚纤维中特异表达

Expression of Lc Gene Driven by a Cotton Fiber Specific Promoter of GhACT1 in Cotton Immature Embryos

【目的】利用现代生物技术获得转基因棉花,是促进改良棉花纤维颜色研究的一个重要途径。【方法】利用农杆菌介导法将棉花纤维特异表达GhACT1启动子驱动下的玉米色素基因Lc转入棉花,经过聚合酶链式反应(Polymerase chain reaction,PCR)、Southern blot检测确认,跟踪观察植株的颜色变化,并对转基因再生株系营养体及幼胚纤维进行逆转录(Reverse transcription,RT)PCR检测,分析该基因在转基因株系中的表达情况。【结果】获得25个转基因株系,观察发现这些株系没有明显的颜色变化。RT-PCR检测结果发现,Lc基因在叶、叶柄及茎中没有表达,而在开花后1~12 d的幼胚及纤维中有较强表达,并且转基因幼胚纤维在离体光照培养1周条件下呈现红色。【结论】GhACT1启动子驱动下的Lc基因在转基因株系中具有幼胚纤维特异表达特性,在离体光照下,能够改变棉花纤维的颜色。说明通过转基因方法改良棉花纤维颜色是有潜力的。

[Objective]To promote the study on color improvement in cotton fiber,it is a key to use transgenic approach.[Method]In this study,the maize Lc gene,under the control of the fiber specific promoter of GhACT1,was introduced into cotton by Agrobacterium-mediated method.The integration of maize Lc gene was confirmed by the polymerase chain reaction(PCR)and southern blot,meanwhile follow-up observation of color change during the transgenic plants growing.The expression of transcription level was analyzed by reverse transcription(RT)-PCR amplification.[Result]Our data showed there were 25 lines of positive plants that had no obvious color change.The expression test results of Lc gene showed that there was no expression signal in vegetative parts,including leaf,petiole and stem.However,there were high expression signals in fiber of ovules at 1―12 days post anthesis in transcription level.The result of culturing in vitro showed that red color appeared on the ovules’surface and the initial fiber turned red under light for 1 week.[Conclusion]The Lc gene driven by the promoter of GhACT1 was introduced into cotton successfully and expressed in ovule and fiber specially,leading to red fiber appeared under light.These data indicate that it is potential to engineer colored fibers through transgenic approach in cotton.