Breindl M, Harbers K, Jaenisch R
Cell. 1984 Aug;38(1):9-16. doi: 10.1016/0092-8674(84)90521-x.
The chromatin structure of the collagen alpha 1(I) gene, which has been mutated by retrovirus insertion in Mov13 mice, was compared with that of the wildtype allele. Limited digestions with DNAase I revealed the presence of two hypersensitive sites in all normal cells analyzed, while a third site at 100 to 200 bp 5' of the transcription start was detected only in cells synthesizing collagen alpha 1(I) mRNA. This transcription-associated site was not present in chromatin of the mutant allele, while the two other hypersensitive sites, one of which is located close to the provirus, were not changed by the virus integration. Our results suggest that the virus insertion in Mov13 mice may prevent the developmentally regulated appearance of a transcription-associated hypersensitive site, thereby interfering with proper activation of the gene during embryonic development.
在Mov13小鼠中，因逆转录病毒插入而发生突变的胶原蛋白α1（I）基因的染色质结构，与野生型等位基因的染色质结构进行了比较。用DNA酶I进行有限消化后发现，在所有分析的正常细胞中都存在两个超敏位点，而仅在合成胶原蛋白α1（I）mRNA的细胞中，才检测到位于转录起始位点5'端100至200 bp处的第三个位点。这个与转录相关的位点在突变等位基因的染色质中不存在，而另外两个超敏位点，其中一个靠近前病毒，并未因病毒整合而改变。我们的结果表明，Mov13小鼠中的病毒插入可能会阻止与转录相关的超敏位点在发育过程中的出现，从而干扰胚胎发育过程中该基因的正常激活。
