A derivative of Tn5 with direct terminal repeats can transpose.
A derivative of Tn5 with direct terminal repeats can transpose.
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具有直接末端重复序列的 Tn5 衍生物可以转座。
DOI：
10.1016/0022-2836(82)90439-9
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发表时间：
1982
影响因子：
5.6
通讯作者：
Berg,DE
中科院分区：
文献类型：
--
作者：
Hirschel,BJ;Berg,DE
5.7kb的可转座卡那霉素抗性决定簇Tn 5含有1.5kb的末端反向重复序列，我们在此称之为臂。Tn 5的臂含有Tn 5转座所必需的基因和位点，并且与先前描述的转座因子不同源。为了确定一个或两个臂是否是转座（IS）元件，我们将Tn 5转座到pBR 322上，并使用限制性内切酶消化和体外连接来产生质粒衍生物，命名为pTn 5-DR 1和pTn 5-DR 2，其中Tn 5的臂以正向而不是反向方向存在。对pTn 5-DR 1质粒二聚体与λ噬菌体的转座产物分析表明，质粒左右臂的内外端均能起转座作用。我们的结论是Tn 5的两个臂都是转座因子，并将它们命名为IS 50 L（左）和IS 50 R（右）。编码转座酶的IS 50 R的使用频率是IS 50 L的几倍，IS 50 L含有转座酶的赭色突变等位基因：这意味着Tn 5的转座酶优先作用于编码它的DNA片段。对转座因子Tn 5-DR 2转座到该操纵子的分析表明，Tn 5-DR 2与野生型Tn 5一样，在插入位点的选择中表现出区域偏好性而没有严格的位点特异性。
The 5.7 kb§transposable kanamycin resistance determinant Tn5 contains 1.5 kb terminal inverted repeats which we here call arms. Tn5's arms contain the genes and sites necessary for Tn5 transposition, and are not homologous to previously described transposable elements. To determine whether one or both arms is a transposable (IS) element, we transposed Tn5 to pBR322 and used restriction endonuclease digestion and ligationin vitroto generate plasmid derivatives designated pTn5-DR1 and pTn5-DR2 in which Tn5's arms were present in direct rather than in inverted orientation. Analysis of transposition products from dimeric forms of the pTn5-DR1 plasmid to phage λ showed that the outside and inside termini of right and of left arms could function in transposition. We conclude that both of Tn5's arms are transposable elements and name them IS50L (left) and IS50R (right). IS50R, which encodes transposase, was used several-fold more frequently than IS50L, which contain an ochre mutant allele of transposase: this implies that Tn5's transposase acts preferentially on the DNA segment which encodes it. Analysis of transpositions of theamprkanrelement Tn5-DR2 to thelacoperon showed that Tn5-DR2, like Tn5 wild-type, exhibits regional preference without strict site specificity in the choice of insertion sites.