L3MBTL1,一个依赖于基因素甲基化的染色体锁定
Patrick Trojer1, Guohong Li, Robert J Sims
1Howard Hughes Medical Institute, University of Medicine and Dentistry of New Jersey, 683 Hoes Lane, Piscataway, NJ 08854, USA.
Cell
|June 2, 2007
概括
恶性脑瘤 (MBT) 蛋白质L3MBTL1与甲基化组织素结合,使核细胞组紧缩以抑制转录. 这种蛋白质将基因基因修饰与基因沉默和异色染色体的形成联系起来.
科学领域:
- 分子生物学分子生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 染色体生物学 染色体生物学
背景情况:
- 基因组甲基化标记调节基因表达和异色染色体的形成.
- 这些标记引发转录抑制的确切机制尚未完全理解.
研究的目的:
- 研究恶性脑瘤 (MBT) 蛋白 L3MBTL1 在转录抑制中的作用.
- 阐明L3MBTL1与基因素修饰相互作用的分子机制.
主要方法:
- 共同免疫沉以确定L3MBTL1相互作用伙伴.
- 核组合压缩试验. 核组合压缩试验.
- 与L3MBTL1和E2F活动相关的基因表达的分析.
主要成果:
- L3MBTL1形成了一个复合体,其中包括核心基因素,基因素H1b,HP1gamma和Rb.
- L3MBTL1的MBT域与单基和二基甲基化素H4氨酸20和素H1b氨酸26结合.
- L3MBTL1通过这些基因组标记来调解核体阵列的紧缩.
- L3MBTL1对E2F控制基因的一个子集进行负调节.
结论:
- L3MBTL1直接将特定的基因素甲基化标记的识别与转录抑制联系起来.
- L3MBTL1在选择性异色素蛋白的形成和维护中起作用.
- 由于L3MBTL1能够同时结合多个核体,这有助于基因沉默机制.
相关概念视频
Histone Modification
The histone proteins have a flexible N-terminal tail extending out from the nucleosome. These histone tails are often subjected to post-translational modifications such as acetylation, methylation, phosphorylation, and ubiquitination. Particular combinations of these modifications form “histone codes” that influence the chromatin folding and tissue-specific gene expression.
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
Spreading of Chromatin Modifications
The histone proteins in the nucleosomes are post-translationally modified (PTM) to increase or decrease access to DNA. The commonly observed PTMs are methylation, acetylation, phosphorylation, and ubiquitination of lysine amino acids in the histone H3 tail region. These histone modifications have specific meaning for the cell. Hence, they are called "histone code". The protein complex involved in histone modification is termed as "reader-writer" complex.
Writers
The writer is an enzyme that can...
Writers
The writer is an enzyme that can...
Euchromatin
The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions take up more dye, appearing darker, while the less-compact areas take up less dye and appear lighter. Based on the compaction level, chromatins are classified into two primary forms – euchromatin and heterochromatin.
Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...
Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...
Heterochromatin
The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions that take up more dye are called heterochromatin. Heterochromatin is further classified into two forms – constitutive heterochromatin and facultative heterochromatin.
Constitutive heterochromatin: It is a highly compact region of chromatin that is mostly concentrated in the centromere and telomere. Unlike euchromatin, the amino acid at 9th...
Constitutive heterochromatin: It is a highly compact region of chromatin that is mostly concentrated in the centromere and telomere. Unlike euchromatin, the amino acid at 9th...
Euchromatin
The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions take up more dye, appearing darker, while the less-compact areas take up less dye and appear lighter. Based on the compaction level, chromatins are classified into two primary forms – euchromatin and heterochromatin.
Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...
Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...
Histone Modification
The histone proteins have a flexible N-terminal tail extending out from the nucleosome. These histone tails are often subjected to post-translational modifications such as acetylation, methylation, phosphorylation, and ubiquitination. Particular combinations of these modifications form “histone codes” that influence the chromatin folding and tissue-specific gene expression.
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...


