转录性沉默基因与Ikaros复合体的关联在中心的异色染色蛋白中
K E Brown1, S S Guest, S T Smale
1Lymphocyte Development Group, MRC Clinical Sciences Centre, Imperial College School of Medicine, Hammersmith Hospital, London, United Kingdom.
Cell
|December 31, 1997
概括
对于免疫细胞发育至关重要的Ikaros蛋白质,意外地与B细胞中密集的DNA区域结合. 这表明被抑制的基因被组织在这些核区内.
科学领域:
- 细胞生物学 细胞生物学
- 免疫学 免疫学 免疫学
- 遗传学 是一个遗传学.
背景情况:
- 伊卡洛斯蛋白对于T,B和NK细胞发育至关重要.
- 他们被认为可以激活淋巴细胞特异性基因表达.
- 伊卡洛斯蛋白的核定位和功能仍然不完全理解.
研究的目的:
- 为了研究B淋巴细胞中Ikaros蛋白的核分布.
- 确定Ikaros与特定核结构和基因位置的关联.
主要方法:
- 使用共聚焦显微镜可视化Ikaros蛋白质定位.
- 开发并使用了一种新的免疫光在位杂交 (免疫-FISH) 技术.
- 用特定位置的探针来检查与Ikaros焦点的基因关联.
主要成果:
- 伊卡洛斯蛋白质意外地定位在B淋巴细胞核中的离散的异染色素含有焦点.
- 这些焦点被确定为中心基DNA的集群,富含 heterochromatin protein-1 (HP-1).
- 转录不活跃的基因 (CD2,CD4,CD8alpha,CD19,CD45,lambda5) 与Ikaros-heterochromatin焦点相关,而活跃的基因没有.
结论:
- 伊卡洛斯蛋白质被招募到核内部的中心性异色染色素域.
- 这种局部化表明,Ikaros在组织特定核区内的抑制基因方面发挥了作用.
- 这些发现支持一个模型,其中核将被压抑的基因组织成中心域.
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