The genomic sequences bound to special AT-rich sequence-binding protein 1 (SATB1) in vivo in Jurkat T cells are tightly associated with the nuclear matrix at the bases of the chromatin loops.
The genomic sequences bound to special AT-rich sequence-binding protein 1 (SATB1) in vivo in Jurkat T cells are tightly associated with the nuclear matrix at the bases of the chromatin loops.
复制标题
在Jurkat T细胞中与特殊富含富含富含良好的序列结合蛋白1（SATB1）结合的基因组序列与染色质环的底部的核基质紧密相关。
DOI：
10.1083/jcb.141.2.335
复制
发表时间：
1998-04-20
影响因子：
7.8
通讯作者：
Kohwi-Shigematsu, T
中科院分区：
文献类型：
--
作者：
de Belle, I;Cai, ST;Kohwi-Shigematsu, T
特殊的富含 AT 的序列结合蛋白 1 (SATB1) 是一种主要在胸腺细胞中表达的 DNA 结合蛋白，可识别 ATC 序列背景，该序列背景由一组序列延伸组成，其中 A、T 和 C 在一条链上充分混合，但不含 G。这些区域赋予稳定碱基不配对的高倾向。使用体内交联策略，单独分离并表征了与人淋巴细胞系 Jurkat 细胞中 SATB1 结合的特殊基因组序列 (0.1–1.1 kbp)。所有检查的体内 SATB1 结合序列都包含典型的 ATC 序列背景，其中一些与来自酿酒酵母的自主复制序列表现出同源性，这些序列在酵母细胞中充当复制起点。此外，还鉴定了 LINE 1 元件、卫星 2 序列和含 CpG 岛的 DNA。为了检查这些体内 SATB1 结合序列的高阶包装，在通过核酸酶消化去除大部分 DNA 后，对带有扩张环的核“晕”和核基质进行了高分辨率原位荧光杂交。体内 SATB1 结合序列与基因组 DNA 杂交，作为由 DNA 晕圈包围的残留核内的单个点，并在核基质中保留为单个点，表明这些序列位于染色质环的底部。在不表达 SATB1 的人乳腺癌 SK-BR-3 细胞中，发现至少有一个这样的序列未锚定在核基质上。这些发现提供了第一个证据，证明细胞类型特异性因子（例如 SATB1）在体内与染色质环的基部结合，并表明特定的染色质环结构域结构参与 T 细胞特异性基因调控。
Special AT-rich sequence-binding protein 1 (SATB1), a DNA-binding protein expressed predominantly in thymocytes, recognizes an ATC sequence context that consists of a cluster of sequence stretches with well-mixed A's, T's, and C's without G's on one strand. Such regions confer a high propensity for stable base unpairing. Using an in vivo cross-linking strategy, specialized genomic sequences (0.1–1.1 kbp) that bind to SATB1 in human lymphoblastic cell line Jurkat cells were individually isolated and characterized. All in vivo SATB1-binding sequences examined contained typical ATC sequence contexts, with some exhibiting homology to autonomously replicating sequences from the yeast Saccharomyces cerevisiae that function as replication origins in yeast cells. In addition, LINE 1 elements, satellite 2 sequences, and CpG island–containing DNA were identified. To examine the higher-order packaging of these in vivo SATB1-binding sequences, high-resolution in situ fluorescence hybridization was performed with both nuclear “halos” with distended loops and the nuclear matrix after the majority of DNA had been removed by nuclease digestion. In vivo SATB1-binding sequences hybridized to genomic DNA as single spots within the residual nucleus circumscribed by the halo of DNA and remained as single spots in the nuclear matrix, indicating that these sequences are localized at the base of chromatin loops. In human breast cancer SK-BR-3 cells that do not express SATB1, at least one such sequence was found not anchored onto the nuclear matrix. These findings provide the first evidence that a cell type–specific factor such as SATB1 binds to the base of chromatin loops in vivo and suggests that a specific chromatin loop domain structure is involved in T cell–specific gene regulation.
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影响因子：
30.8
作者：
BAXENDALE, S;MACDONALD, ME;BATES, GP
通讯作者：
BATES, GP
影响因子：
64.5
作者：
DICKINSON, LA;JOH, T;KOHWISHIGEMATSU, T
通讯作者：
KOHWISHIGEMATSU, T
影响因子：
64.5
作者：
GASSER, SM;LAEMMLI, UK
通讯作者：
LAEMMLI, UK
影响因子：
4
作者：
CROSS, SH;BIRD, AP
通讯作者：
BIRD, AP
影响因子：
30.8
作者：
CROSS, SH;CHARLTON, JA;BIRD, AP
通讯作者：
BIRD, AP