Lichtenberg U, Zock C, Doerfler W
J Virol. 1987 Sep;61(9):2719-26. doi: 10.1128/JVI.61.9.2719-2726.1987.
In the adenovirus type 12 (Ad12)-induced hamster tumor T1111(2) about 10 Ad12 genome equivalents were integrated at different sites. One of the integrated copies proved unstable and was lost from the cellular genome or rearranged upon passage of the cell line, H1111(2), established from this tumor. This unstable site of junction between the left terminus of Ad12 DNA and hamster DNA and the preinsertion site from BHK21 hamster cells was cloned, sequenced, and analyzed. The junction site showed several peculiarities. At the left terminus of Ad12 DNA, the first 64 nucleotides were deleted. At a distance of 127 nucleotides to the left from this junction site, an internal dispersed fragment of Ad12 DNA comprising nucleotides 1290 to 1361 of the authentic Ad12 DNA sequence was inserted into cellular DNA in an inverted orientation relative to the complete Ad12 genome that was located in its vicinity. The 127-nucleotide sequence between the intact Ad12 genome and the separate 72-base-pair (bp) Ad12 DNA fragment was cellular, but it was not identical to the preinsertion sequence at this location. The sequences flanking the termini of the dispersed 72-bp Ad12 DNA fragment were characterized by direct repeats of 9 or 10 nucleotides. To the left of Ad12 nucleotide 1361 in the separate 72-bp fragment, about 620 cellular nucleotides followed which were identical at the occupied and at the preinsertion sites. It was conceivable that the separate 72-bp Ad12 DNA fragment and the cellular sequence of 127 bp to its right had been transposed en bloc from another unknown location. Abutting the 620 nucleotides of cellular DNA to the left of this block, the 3'-terminal sequence of an endogenous, intracisternal A particle (IAP) genome of hamster cells was detected. The possible significance of the proximity of an IAP sequence to an inserted Ad12 genome with respect to the transformation event, to the instability at this site, or to the transcriptional activity of this region is not known. The 620 bp of cellular DNA between the 72-bp Ad12 DNA fragment and the end of the long terminal repeat of the hamster IAP sequence was apparently of a unique type. Transcriptional activity was not found in the approximate region between nucleotides -620 (to the left) and +350 (to the right) relative to the site of Ad12 DNA insertion, but was found outside these boundaries.
在12型腺病毒（Ad12）诱导的仓鼠肿瘤T1111(2)中，约10个Ad12基因组当量整合于不同位点。其中一个整合拷贝被证明不稳定，在从该肿瘤建立的细胞系H1111(2)传代时从细胞基因组中丢失或发生重排。对Ad12 DNA左末端与仓鼠DNA之间的不稳定连接位点以及来自BHK21仓鼠细胞的预插入位点进行了克隆、测序和分析。连接位点表现出几个独特之处。在Ad12 DNA的左末端，最初的64个核苷酸缺失。在距该连接位点左侧127个核苷酸处，一个包含真实Ad12 DNA序列第1290至1361位核苷酸的Ad12 DNA内部分散片段以相对于其附近完整Ad12基因组的反向方向插入细胞DNA中。完整Ad12基因组与单独的72碱基对（bp）Ad12 DNA片段之间的127核苷酸序列是细胞序列，但与该位置的预插入序列不同。分散的72 bp Ad12 DNA片段末端两侧的序列以9或10个核苷酸的直接重复为特征。在单独的72 bp片段中Ad12核苷酸1361左侧，约620个细胞核苷酸之后，这些核苷酸在占据位点和预插入位点是相同的。可以设想，单独的72 bp Ad12 DNA片段及其右侧127 bp的细胞序列是从另一个未知位置整体转座而来的。在该片段左侧与620个细胞DNA核苷酸相邻处，检测到仓鼠细胞内源性胞内A颗粒（IAP）基因组的3'末端序列。IAP序列与插入的Ad12基因组接近对于转化事件、该位点的不稳定性或该区域的转录活性的可能意义尚不清楚。72 bp Ad12 DNA片段与仓鼠IAP序列长末端重复序列末端之间的620 bp细胞DNA显然是一种独特类型。相对于Ad12 DNA插入位点，在核苷酸-620（左侧）至+350（右侧）的大致区域内未发现转录活性，但在这些边界之外发现了转录活性。
