Conservation of the primary structure, organization, and function of the human and mouse beta-globin locus-activating regions.
Conservation of the primary structure, organization, and function of the human and mouse beta-globin locus-activating regions.
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人类和小鼠 β-珠蛋白位点激活区域的一级结构、组织和功能的保护。
DOI：
10.1073/pnas.87.19.7693
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发表时间：
1990
影响因子：
11.1
通讯作者：
Ley,TJ
中科院分区：
文献类型：
--
作者：
Moon,AM;Ley,TJ
位于人ε-珠蛋白基因上游6-18个碱基（kb）区域的DNA序列被称为基因座激活区（LAR）或显性控制区。该区域被认为在红细胞发育期间在β样珠蛋白基因簇的染色质组织中起关键作用。β-珠蛋白LAR激活瞬时或稳定转染的红白血病细胞和转基因小鼠红系细胞中的连锁珠蛋白基因。由于人类β-珠蛋白LAR在小鼠中具有功能，我们推断关键的LAR序列元件可能在小鼠和人类之间是保守的。因此，我们克隆了与人LAR的一部分同源的鼠基因组序列（位点II，相对于人LAR基因的位置-11，054至-10，322）。我们发现，这种小鼠的DNA片段（小鼠LAR网站II）和序列同源的人类LAR网站I和III位于上游的小鼠β-样珠蛋白基因簇，并确定其位置相对于集群是类似的，他们的人类同行。小鼠和人类之间的同源位点II序列在大约800个碱基对的延伸上有70%相同。在该区域内存在具有大于80%同一性的多个核心序列。K562红白血病细胞的瞬时和稳定转染试验表明，人类和小鼠LAR元件都含有增强子活性，并赋予连接的人γ-珠蛋白启动子上的氯化血红素诱导。这些结果表明，初级结构元素-和这些元素的空间组织-是重要的β-珠蛋白LAR的功能。
DNA sequences located in a region 6-18 kilobases (kb) upstream from the human epsilon-globin gene are known as the locus-activating region (LAR) or dominant control region. This region is thought to play a key role in chromatin organization of the beta-like globin gene cluster during erythroid development. The beta-globin LAR activates linked globin genes in transiently or stably transfected erythroleukemia cells and in erythroid cells of transgenic mice. Since the human beta-globin LAR is functional in mice, we reasoned that critical LAR sequence elements might be conserved between mice and humans. We therefore cloned murine genomic sequences homologous to one portion of the human LAR (site II, positions -11,054 to -10,322 with respect to the human epsilon gene). We found that this murine DNA fragment (mouse LAR site II) and sequences homologous to human LAR sites I and III are located upstream from the mouse beta-like globin gene cluster and determined that their locations relative to the cluster are similar to that of their human counterparts. The homologous site II sequences are 70% identical between mice and humans over a stretch of approximately 800 base pairs. Multiple core sequences with greater than 80% identity were present within this region. Transient and stable transfection assays of K562 erythroleukemia cells demonstrated that both human and mouse LAR elements contain enhancer activity and confer hemin inducibility on a linked human gamma-globin promoter. These results suggest that primary structural elements--and the spatial organization of these elements--are important for function of the beta-globin LAR.