摘要
应用启动子筛选载体（Promoter-trapvector）pLX2A构建了1个黑曲霉（Asperyillusniger）基因组文库。这个载体含有1个潮霉素B（Hy）磷酸转移酶编码基因（hph），它能以启动子活性选择DNA片段。用这个基因组文库转化大肠杆菌，获得了80000转化子菌落，其中94％含有插入片段。用这个基因库的质粒DNA转化黑曲霉，产生了53个抗潮霉素B（HyR）菌落。21个转化子的Southern杂交分析证明，hph基因已整合到黑曲霉基因组上。用同胞选择法（Sibselection）从此基因库中识别出1个有功能的启动子PX27，并测出了其2条DNA链的序列。它的序列与已知数据库中的序列没有明显的相似性。与已知黑曲霉启动子序列的比较分析得知，黑曲霉启动子含有共同序列CTTCTC，或许这个共同序列对黑曲霉启动子的结构是重要的。
An Aspergillus niger (A. niger) genomic library was constructed in a promoter-trap vector, which contains a Hygromycin B (Hy) phosphotransferase-encoding gene (hph) and screened for DNA fi'agmentS with promoter achvity by aPPlying the sibselection procedure. A functional promoter PX27 was identified. Both DNA strands of this fragment were sequenced and showed no significant homology to the sequence already in the database. Comparison of the sequences of all known promoters from A.niger revealed a consensus CTTCTC, as a novel mob f of the A. niger promoters.
关键词
黑曲霉
启动子
筛选载体
克隆
序列特征
Aspergillus niger
Promoter
Hygromycin
Transformation
Promoter-trap vector
Sib selection
