Despite the importance of aloe in cosmetic and pharmaceutical industries, improvement of aloe （Aloe barbadensis Miller） by genetic engineering was seldom reported previously. In this study, regeneration and transformation conditions, including explant selection and surface sterilization, use of different Agrobacterium strains, and co-culture processing, are optimized. The use of 20.0% sodium hypochloride （25 rain） for sterilization was less detrimental to the health of explant than 0.1% mercuric chloride （10 min）. Regeneration frequency from stems was much higher than that from leaves or sheaths. Explants were infected by Agrobacterium （30 rain） in liquid co-cultural medium, and this was followed by three days co-culture on sterile filter papers with light for 10 h per day at 24℃. Histochemical data demonstrated that the transient expression of GUS gene in the stem explants of aloe infected with Agrobacterium strains EHAI05 and C58CI was 80.0% and 30.0%, respectively, suggesting the higher sensitivity of the explants to EHAI05 than to C58C1. Infected tissues were selected using G418 （10.0-25.0 mg/L） to generate transformants. Sixty-seven G418 resistant plantlets were generated from the infected explants. Southern blotting, PCR, and ELISA analyses indicated that the alien gene were successfully transferred into aloe and was expressed in the transgenic plants. This newly established transformation system could be used for the genetic improvement of aloe.
由于芦荟具有医疗、美容、保健、食用等多种功能,近年来成为研究热点.海藻糖对生物体及生物分子具有良好的非特异性保护作用,并已在食品、化妆品、分子生物学领域得到了广泛应用.将海藻糖合成酶基因转入芦荟,对于改良芦荟的商业价值有重要意义.目前为止,关于芦荟转化还没有报道.本实验将含有海藻糖合成酶otsA基因的pBI-otsA质粒与含有bar基因的pAHC25质粒混合包埋金粉子弹,利用基因枪介导的共转化法轰击预培养4～5 d的芦荟茎部外植体,经在含1.0～2.0 mg/ L glufosinate筛选剂的改良MS培养基上多次筛选和分化,获得了一定数量的抗性再生芽,对移栽成活的抗性再生植株进行了PCR检测.结果表明,otsA基因、nptII基因、bar基因已经整合到芦荟基因组中,首次获得了芦荟转基因植株.
