HUMAN HOMOLOGS OF TU TRANSPOSON SEQUENCES - POLYPURINE POLYPYRIMIDINE SEQUENCE ELEMENTS THAT CAN ALTER DNA CONFORMATION INVITRO AND INVIVO
HUMAN HOMOLOGS OF TU TRANSPOSON SEQUENCES - POLYPURINE POLYPYRIMIDINE SEQUENCE ELEMENTS THAT CAN ALTER DNA CONFORMATION INVITRO AND INVIVO
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DOI：
10.1128/mcb.6.11.3632
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发表时间：
1986-11-01
影响因子：
5.3
通讯作者：
COHEN, SN
中科院分区：
文献类型：
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作者：
HOFFMANLIEBERMANN, B;LIEBERMANN, D;COHEN, SN
我们之前已经证明，海胆TU转座子反向重复末端（IVR-OD）外域片段的同源物在包括人类在内的多种真核物种中是保守的。我们在这里报道了两个克隆的人类DNA IVR-OD同源物Hut2和Hut17，由三聚体AGG/TCC的一系列串联重复组成，在两条DNA链中形成多聚嘌呤/多聚嘧啶（pPu/pPy或“Puppy”）不对称片段（长度分别为313和221个碱基对）；这些在某些位点上被变异三聚体打断，这对于两个克隆来说是不同的。与 Hut2 pPu/pPy 序列同源的序列存在于多种真核生物 DNA 的多个位点。人类 DNA 与 Hut2 探针或与先前描述的鸡 DNA pPu/pPy 序列的杂交表明，pPu/pPy 序列可分为可通过其在不同杂交严格度下与每个探针的同源性程度来区分的家族。此外，特定的 pPu/pPy 区域在分布上表现出物种特异性差异。当在超螺旋质粒上进行测试时，Hut2 和 Hut17 pPu/pPy 片段均被 S1 核酸酶切割。大多数（如果不是全部）313 碱基对 Hut2 pPu/pPy 序列也对 HeLa 细胞染色质中天然位置的 S1 敏感，表明该序列包含可以在体内表达的构象信息。这一观点得到了证据的支持，即引入小鼠 L 细胞并整合到染色质中的外源衍生 Hut2 pPu/pPy 束可以呈现 S1 敏感构象。
We previously have shown that homologs of the outer domain segment of the inverted repeat termini (IVR-OD) of the sea urchin TU transposons are conserved among multiple eucaryotic species, including humans. We report here that two cloned human DNA IVR-OD homologs, Hut2 and Hut17, consist of a series of tandem repeats of the trimer AGG/TCC, forming segments (313 and 221 base pairs in length, respectively) of polypurine/polypyrimidine (pPu/pPy or "Puppy") asymmetry in the two DNA strands; these are punctuated at certain sites with variant trimers, which are different for the two clones. Sequences homologous to the Hut2 pPu/pPy tract exist at multiple sites in the DNA of a wide variety of eucaryotes. Hybridization of human DNA with a Hut2 probe or with a previously described chicken DNA pPu/pPy sequence indicates that pPu/pPy sequences can be grouped into families distinguishable by the extent of their homology with each probe at different hybridization stringencies. Moreover, particular pPu/pPy tracts show species-specific differences in their distribution. Both the Hut2 and Hut17 pPu/pPy tracts are cleaved by S1 nuclease when tested on supercoiled plasmids. Most if not all of the 313-base-pair Hut2 pPu/pPy tract is also sensitive to S1 in its native location in HeLa cell chromatin, indicating that the sequence contains conformational information that can be expressed in vivo. This view is supported by evidence that exogenously derived Hut2 pPu/pPy tracts introduced into mouse L cells and integrated in chromatin can assume an S1-sensitive conformation.