Nuclease sensitivity of the mouse HPRT gene promoter region: differential sensitivity on the active and inactive X chromosomes.
Nuclease sensitivity of the mouse HPRT gene promoter region: differential sensitivity on the active and inactive X chromosomes.
复制标题
小鼠 HPRT 基因启动子区域的核酸酶敏感性：活性和非活性 X 染色体的敏感性差异。
DOI：
10.1128/mcb.7.8.2994-2998.1987
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发表时间：
1987
影响因子：
5.3
通讯作者：
Caskey,CT
中科院分区：
文献类型：
--
作者：
Yang,TP;Caskey,CT
我们研究了X连锁小鼠次黄嘌呤鸟嘌呤磷酸核糖转移酶基因（HPRT）启动子区的构象，无论是在染色质中的活性和非活性X染色体与DNase I和裸超螺旋DNA与S1核酸酶。用DNase I同时处理小家鼠（Mus musculus）和小家鼠（Mus caroli）种间杂种细胞核中的活性和非活性X染色体，直接比较了小鼠HPRT启动子活性区和非活性区的染色质结构。使用限制性片段长度多态性来区分活跃和不活跃的HPRT启动子，我们发现了一个小的，但非常明显的差异，在DNase I敏感性的活性与不活跃的染色质。我们还观察到一个单一的DNA酶I-超敏感位点的直接区域的启动子，这是目前只在活跃的X染色体。通过S1核酸酶消化超螺旋质粒DNA的启动子区域的分析显示，S1敏感位点映射在染色质中发现的DNA酶I超敏感位点附近或之内，但在正常HPRT基因表达所需的最低限度区域的上游。
We investigated the conformation of the X-linked mouse hypoxanthine-guanine phosphoribosyltransferase gene (HPRT) promoter region both in chromatin from the active and inactive X chromosomes with DNase I and in naked supercoiled DNA with S1 nuclease. A direct comparison of the chromatin structures of the active and inactive mouseHPRTpromoter regions was performed by simultaneous DNase I treatment of the active and inactive X chromosomes in the nucleus of interspecies hybrid cells fromMus musculusandMus caroli. Using a restriction fragment length polymorphism to distinguish between the active and inactiveHPRTpromoters, we found a small but very distinct difference in the DNase I sensitivity of active versus inactive chromatin. We also observed a single DNase I-hypersensitive site in the immediate area of the promoter which was present only on the active X chromosome. Analysis of the promoter region by S1 nuclease digestion of supercoiled plasmid DNA showed an S1-sensitive site which maps adjacent to or within the DNase I-hypersensitive site found in chromatin but upstream of the region minimally required for normalHPRTgene expression.