Recombination by resolvase is inhibited by lac repressor simultaneously binding operators between res sites.
Recombination by resolvase is inhibited by lac repressor simultaneously binding operators between res sites.
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解离酶的重组被 lac 阻遏物同时结合 res 位点之间的操纵子所抑制。
DOI：
10.1016/0022-2836(87)90028-3
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发表时间：
1987
影响因子：
5.6
通讯作者：
Fennewald,M
中科院分区：
文献类型：
--
作者：
Saldanha,R;Flanagan,P;Fennewald,M
Tn3 解离酶要求两个重组 (res) 位点在同一分子上对齐为直接重复序列，以实现有效的重组。为了测试解离酶是否必须如跟踪模型所预测的那样接触位点之间的 DNA，我们确定了重组对蛋白质扩散阻断的敏感性。两个位点之间的重组不受它们之间结合的lacrepressor或噬菌体T7 RNA聚合酶的影响。然而，如果 ressite 的两侧都受到 alacoperator 的限制，则重组会被 lacrepressor 抑制。我们证明，在用于测定重组的条件下，lacrepressor 将结合多个 DNA 位点。该结果表明，lacrepressor 可以通过形成在拓扑上隔离 aressite 的 DNA 环来抑制拆分酶。这些结果不支持拆分酶的跟踪模型，但表明 DNA 底物的结构和拓扑对于ressites 之间突触的形成很重要。
The Tn3 resolvase requires that the two recombination (res) sites be aligned as direct repeats on the same molecule for efficient recombination to occur. To test whether resolvase must contact the DNA betweenressites as predicted by tracking models, we have determined the sensitivity of recombination to protein diffusion blockades. Recombination between tworessites is unaffected either bylacrepressor or bacteriophage T7 RNA polymerase being bound between them. Yet recombination is inhibited bylacrepressor if theressite is bounded by alacoperator on both sides. We demonstrate thatlacrepressor will bind to more than one DNA site under the conditions used to assay recombination. This result suggests thatlacrepressor can inhibit resolvase by forming a DNA loop that isolates aressite topologically.These results do not support a tracking model for resolvase but suggest that the structure and topology of the DNA substrate is important in the formation of a synapse betweenressites.