Tsutsumi K, Tsutsumi R, Ishikawa K
Department of Biochemistry, Yamagata University School of Medicine.
J Biochem. 1987 Nov;102(5):1013-21. doi: 10.1093/oxfordjournals.jbchem.a122139.
Chromatin structures of the aldolase B gene locus in repressed and derepressed states were examined by DNase I digestion. Within the gene locus, several structural features were observed with respect to the sensitivity to DNase I; hypersensitive sites, relatively resistant regions, and preferential cleavage sites within the resistant regions. The hypersensitive sites and the resistant regions are tissue- or cell-specifically distributed, but are not simply related to the active or inactive state chromatin. Among these structural features, however, a DNase I-hypersensitive site located about 0.3 kilobase pairs (kb) upstream from the transcription-initiation site is characteristic only in transcriptionally active tissues or cells (liver, kidney and Morris hepatoma 5123D). In addition, analysis with nuclei of fetal liver cells indicated that this hypersensitive site is constructed prior to the transcriptional activation of the aldolase B gene during development. These results may indicate that the structural alteration in chromatin at the 0.3 kb upstream site is related to the regulation of the aldolase B gene expression.
通过DNA酶I消化检测醛缩酶B基因位点在抑制和去抑制状态下的染色质结构。在基因位点内，观察到了一些关于对DNA酶I敏感性的结构特征；超敏感位点、相对抗性区域以及抗性区域内的优先切割位点。超敏感位点和抗性区域在组织或细胞中具有特异性分布，但并不简单地与染色质的活性或非活性状态相关。然而，在这些结构特征中，位于转录起始位点上游约0.3千碱基对（kb）处的一个DNA酶I超敏感位点仅在转录活跃的组织或细胞（肝脏、肾脏和莫里斯肝癌5123D）中具有特征性。此外，对胎肝细胞细胞核的分析表明，在发育过程中，该超敏感位点在醛缩酶B基因转录激活之前就已形成。这些结果可能表明，上游0.3 kb处染色质的结构改变与醛缩酶B基因表达的调控有关。
