利用PCR方法克隆了香蕉束顶病毒中国漳州分离物(BBTV-ZZ)DNA 4编码区,序列分析结果表明该编码区由351个核苷酸组成,推测其编码是一个含116个氨基酸的蛋白质,利用植物双元载体pBin438构建了含有BBTV-ZZ DNA 4编码区的植物组成型表达载体pBBTV-4B,经农杆菌介导转化了三生烟(Nicotiana tabacum Xanthi nc),在防虫条件下,将运动缺陷型CMV-Fny突变株(CMV-Fny-△MP)人工接种到转基因植株下部叶片上,12d后,在转基因植株的非接种叶上显现出不同程度的系统侵染症状,间接异种动物双抗体夹心酶联免疫吸附方法(DAS-ELISA)检测结果显示在转基因植株的上部非接种叶中有CMV-Fny的积累,而非转基因对照植株组的上部非接种叶中始终没有显现系统侵染症状,DAS-ELISA检测也未见CMV-Fny的积累,这些实验结果表明转基因植株能够支持CMV-Fny-△Mp从细胞到细胞和长距离运动并形成系统侵染症状,由此推测BBTV-ZZ DNA 4编码的蛋白质可能具有运动蛋白功能。
Banana bunchy top virus disease (BBTD) is a disastrous disease in bananas, and it is spreading in the world (including China) by the banana bunchy top virus(BBTV). At present, virus\|free plantlets are used to prevent BBTD in banana production, therefore, it is very important to establish a method to detect BBTV quickly, sensitively and specifically. ELISA is now popularly used to detect BBTV. The sensitivity of this method is not high enough, and needs specific antiserum, otherwise, pseudo\|positive results often occur. According to DNA coding sequences of component Ⅲ,Ⅳ and Ⅰ of BBTV isolates from Zhangzhou, China, three pairs of primers are designed to establish a PCR method to specifically amplify parts of coding sequences of the BBTV coat protein, movement protein and replicase\|association. This method is also applicable to detect BBTV of bananas or cultured banana seedlings in other regions.
