Methylation of the minimal promoter of an embryonic globin gene silences transcription in primary erythroid cells.
Methylation of the minimal promoter of an embryonic globin gene silences transcription in primary erythroid cells.
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胚胎球蛋白基因最小启动子的甲基化使原代红系细胞中的转录沉默。
DOI：
10.1073/pnas.94.25.13724
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发表时间：
1997
影响因子：
11.1
通讯作者：
Ginder,GD
中科院分区：
文献类型：
--
作者：
Singal,R;Ferris,R;Little,JA;Wang,SZ;Ginder,GD
二核苷酸CpG中胞嘧啶的甲基化已被证明可以抑制许多组织特异性基因的转录，但其确切机制尚不完全清楚。脊椎动物珠蛋白基因是第一个在CpG甲基化和转录之间显示负相关的例子。我们利用亚硫酸氢钠转化技术研究了原代鸡红系细胞基因组DNA中235 bp的ρ-珠蛋白基因启动子的甲基化模式，发现该启动子的所有CpGs在成年鸡红系细胞中都被甲基化，而在5天（原始）胚胎红细胞中，ρ-珠蛋白基因是沉默的，而在基因转录的红系细胞中未甲基化。为了进一步阐明甲基化诱导沉默的机制，我们将一个含有235 bp的ρ-珠蛋白基因5′启动子序列和一个驱动氯霉素乙酰转移酶报告基因ρ-CAT的强5′红系增强子转染到5天胚的原代禽红系细胞中。每个CpG上235 bp的ρ-珠蛋白基因启动子片段的甲基化导致20- 30倍的转录抑制，并且这种效应不会被强效红细胞特异性增强子的存在所覆盖。利用原代禽红细胞细胞核提取物，用电泳迁移位移法检测了235 bp的ρ-珠蛋白基因启动子与脱氧甲基胞嘧啶结合蛋白复合物（MeCPC）的结合能力。结果表明，完全甲基化而非未甲基化的235 bp ρ-珠蛋白基因启动子片段能够有效地竞争MeCPC结合。这些结果直接证明了球蛋白基因启动子在体内甲基化的CpGs上的位点特异性甲基化可以沉默同源原代红细胞的转录。此外，这些数据暗示了MeCPC与启动子的结合在沉默机制中。
Methylation of cytosines in the dinucleotide CpG has been shown to suppress transcription of a number of tissue-specific genes, yet the precise mechanism is not fully understood. The vertebrate globin genes were among the first examples in which an inverse correlation was shown between CpG methylation and transcription. We studied the methylation pattern of the 235-bp ρ-globin gene promoter in genomic DNA from primary chicken erythroid cells using the sodium bisulfite conversion technique and found all CpGs in the promoter to be methylated in erythroid cells from adult chickens in which the ρ-globin gene is silent but unmethylated in 5-day (primitive) embryonic red cells in which the gene is transcribed. To elucidate further the mechanism of methylation-induced silencing, an expression construct consisting of 235 bp of 5′ promoter sequence of the ρ-globin gene along with a strong 5′ erythroid enhancer driving a chloramphenicol acetyltransferase reporter gene, ρ-CAT, was transfected into primary avian erythroid cells derived from 5-day embryos. Methylation of just the 235-bp ρ-globin gene promoter fragment at every CpG resulted in a 20- to 30-fold inhibition of transcription, and this effect was not overridden by the presence of potent erythroid-specific enhancers. The ability of the 235-bp ρ-globin gene promoter to bind to a DNAMethylCytosine bindingProteinComplex (MeCPC) was tested in electrophoretic mobility shift assays utilizing primary avian erythroid cell nuclear extract. The results were that fully methylated but not unmethylated 235-bp ρ-globin gene promoter fragment could compete efficiently for MeCPC binding. These results are a direct demonstration that site-specific methylation of a globin gene promoter at the exact CpGs that are methylatedin vivocan silence transcription in homologous primary erythroid cells. Further, these data implicate binding of MeCPC to the promoter in the mechanism of silencing.
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人类白细胞抗原 E 基因的干扰素 γ 诱导是通过含有 STAT1α 的复合物与独特的干扰素 γ 响应元件结合介导的*
影响因子：
4.8
作者：
K. Gustafson;G. Ginder
通讯作者：
G. Ginder
小鼠鸡β-珠蛋白基因簇上游过敏位点的功能。
影响因子：
14.9
作者：
M. Reitman;E. Lee;H. Westphal
通讯作者：
H. Westphal
鸡胚胎血红蛋白的结构研究。
DOI：
10.1016/s0021-9258(19)42568-4
发表时间：
1974
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
J. Brown;V. Ingram
通讯作者：
V. Ingram
禽类 40 KDa 核蛋白优先结合包含一对甲基化 CpG 的启动子序列。
影响因子：
14.9
作者：
André Pawlak;Margaret Bryans;Jean
通讯作者：
Jean
组蛋白 H1 介导的体外甲基化模板转录起始抑制。
DOI：
--
发表时间：
1993
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Levine,A;Yeivin,A;Ben-Asher,E;Aloni,Y;Razin,A
通讯作者：
Razin,A