Kawasaki K, Takahashi M, Natori M, Shibata T
Laboratory of Microbiology, Riken Institute, Saitama, Japan.
J Biol Chem. 1991 Mar 15;266(8):5342-7.
A eukaryotic sequence-specific endonuclease, Endo.SceI, causes sequence-specific double-stranded scission of double-stranded DNA to produce cohesive ends with four bases protruding at the 3' termini. Unlike in the case of restriction enzymes, an asymmetric 26-base pair consensus sequence was found around the cleavage site for Endo.SceI instead of a common sequence. We analyzed the base pairs that interacted with Endo.SceI on the recognition of its cleavage sites. A region comprising -10 through +16 base pairs from the center of the cleavage site was shown to be essential and sufficient for the sequence-specific cutting with Endo.SceI by experiments involving synthesized DNAs. Methylation interference experiments indicate that bases in the region comprising the +7 through +14 base pairs is involved in close contact with Endo.SceI in its recognition of the cleavage site. This +7 through +14-base pair region overlaps the most stringently conserved sequence in the consensus sequence for the cleavage site, suggesting that this region constitutes the core for the recognition by Endo.SceI.
一种真核生物序列特异性核酸内切酶Endo.SceI，可导致双链DNA发生序列特异性双链断裂，产生在3'末端突出四个碱基的粘性末端。与限制酶的情况不同，在Endo.SceI的切割位点周围发现的是一个不对称的26碱基对共有序列，而非共同序列。我们分析了在识别切割位点时与Endo.SceI相互作用的碱基对。通过涉及合成DNA的实验表明，从切割位点中心起包含-10至+16碱基对的区域对于Endo.SceI进行序列特异性切割至关重要且足够。甲基化干扰实验表明，包含+7至+14碱基对的区域中的碱基在Endo.SceI识别切割位点时与其紧密接触。这个+7至+14碱基对区域与切割位点共有序列中最严格保守的序列重叠，表明该区域构成了Endo.SceI识别的核心。
