TRANSPOSON TN7 CIS-ACTING SEQUENCES IN TRANSPOSITION AND TRANSPOSITION IMMUNITY
TRANSPOSON TN7 CIS-ACTING SEQUENCES IN TRANSPOSITION AND TRANSPOSITION IMMUNITY
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DOI：
10.1016/0022-2836(89)90439-7
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发表时间：
1989-05-05
影响因子：
5.6
通讯作者：
CRAIG, NL
中科院分区：
文献类型：
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作者：
ARCISZEWSKA, LK;DRAKE, D;CRAIG, NL
我们已经确定并表征了细菌转座子Tn7末端的顺式作用重复序列，这是其转座所必需的。Tn7参与两种类型的转座事件：高频转座到特定的靶位点（attTn7）和低频转座到明显随机的靶位点。我们的分析表明，在Tn7末端的相同序列所需的两个转座事件。这些序列在长度和核苷酸结构上不同：左端约150个碱基对（Tn7L）和右端约70个碱基对（Tn7R）是有效转座所必需的。我们还表明，Tn7的两端是功能不同的：一个迷你Tn7元件含有两个Tn7R端是积极的转座，但一个元件含有两个Tn7L端不是。我们还报道了Tn7的顺式作用转座序列在靶复制子中的任何位置的存在抑制了随后Tn7的另一个拷贝插入attTn7靶位点或随机靶位点。当Tn7末端紧邻attTn7时，对attTn7靶位点的抑制最明显。我们还表明，目标复制子中Tn7 R '的顺式作用转座序列的存在对于抑制随后的Tn7插入目标复制子是必要且足够的。
We have identified and characterized the cis-acting seuqences at the termini of the bacterial transposon Tn7 that are necessary for its transposition. Tn7 participates in two kinds of transposition event: high-frequency transposition to a specific target site (attTn7) and low-frequency transposition to apparently random target sites. Our analyses suggest that the same sequences at the Tn7 ends are required for both transposition events. These sequences differ in length and nucleotide structure: about 150 base-pairs at the left end (Tn7L) and about 70 base-pairs at the right end (Tn7R) are necessary for efficient transposition. We also show that the ends of Tn7 are functionally distinct: a mini Tn7 element containing two Tn7R ends is active in transposition but an element containing two Tn7L ends is not. We also report that the presence of Tn7''s cis-acting transposition sequences anywhere in a target replicon inhibits subsequent insertion of another copy of Tn7 into either an attTn7 target site or into random target sites. The inhibition to an attTn7 target site is most pronounced when the Tn7 ends are immediately adjacent to attTn7. We also show that the presence of Tn7R''s cis-acting transposition sequences in a target replicon is necessary and sufficient to inhibit subsequent Tn7 insertion into the target replicon.