The Human GATA1 Gene Retains a 5' Insulator That Maintains Chromosomal Architecture and GATA1 Expression Levels in Splenic Erythroblasts.
The Human GATA1 Gene Retains a 5' Insulator That Maintains Chromosomal Architecture and GATA1 Expression Levels in Splenic Erythroblasts.
复制标题
人类 GATA1 基因保留了 5 绝缘体，可维持脾成红细胞中的染色体结构和 GATA1 表达水平。
DOI：
10.1128/mcb.00011-15
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
Yamamoto M.
中科院分区：
文献类型：
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作者：
Moriguchi T;Yu L;Takai J;Hayashi M;Satoh H;Suzuki M;Ohneda K;Yamamoto M.
GATA 1是红细胞生成的关键转录因子，其基因表达在转录水平受到严格调控。虽然小鼠Gata 1（mGata 1）基因表达的调控机制已被广泛研究，如何表达的humanGATA 1（hGATA 1）基因的调控仍有待阐明。为了解决这一问题，我们建立了dhGATA 1细菌人工染色体（BAC）转基因小鼠系，该转基因小鼠含有一个183-kbhGATA 1基因座，覆盖hGATA 1外显子和远端侧翼序列。转基因GATA 1表达与内源性GATA 1表达一致，并完全挽救mGATA 1敲除小鼠的造血缺陷。转基因表现出拷贝数依赖性和整合位置无关的hGATA 1表达，表明转基因内存在染色质绝缘子活性。我们在hGATA 1基因5′端29 kb处发现了一个新的绝缘子元件，并将其命名为5′ CCCTC结合因子（CTCF）位点。hGATA 1BAC基因5′ CTCF位点的突变破坏了脾成红细胞的染色质结构，并导致应激红细胞生成条件下hGATA 1的表达减少。我们的研究结果表明hGATA 1基因的表达是通过hGATA 1基因座上5′ CTCF位点介导的染色体内相互作用组织的染色质结构来调节的。
GATA1 is a key transcription factor for erythropoiesis.GATA1gene expression is strictly regulated at the transcriptional level. While the regulatory mechanisms governing mouseGata1(mGata1) gene expression have been studied extensively, how expression of the humanGATA1(hGATA1) gene is regulated remains to be elucidated. To address this issue, we generatedhGATA1bacterial artificial chromosome (BAC) transgenic mouse lines harboring a 183-kbhGATA1locus covering thehGATA1exons and distal flanking sequences. TransgenichGATA1expression coincides with endogenousmGata1expression and fully rescues hematopoietic deficiency inmGata1knockdown mice. The transgene exhibited copy number-dependent and integration position-independent expression ofhGATA1, indicating the presence of chromatin insulator activity within the transgene. We found a novel insulator element at 29 kb 5′ to thehGATA1gene and refer to this element as the 5′ CCCTC-binding factor (CTCF) site. Substitution mutation of the 5′ CTCF site in thehGATA1BAC disrupted the chromatin architecture and led to a reduction ofhGATA1expression in splenic erythroblasts under conditions of stress erythropoiesis. Our results demonstrate that expression of thehGATA1gene is regulated through the chromatin architecture organized by 5′ CTCF site-mediated intrachromosomal interactions in thehGATA1locus.