一个染色质重塑复合物,它将凝聚素加载到人类染色体上
Mohamed-Ali Hakimi1, Daniel A Bochar, John A Schmiesing
1The Wistar Institute, 3601 Spruce Street, Philadelphia, Pennsylvania 19104, USA.
Nature
|August 29, 2002
概括
这项研究确定了一种新型的人类染色体重塑复合物,该复合物含有SNF2h和凝聚素成分. 这种复合物促进了对核细胞DNA的获取,这对于DNA-蛋白相互作用和染色体分离至关重要.
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:
- 核体DNA的高阶结构阻碍了蛋白质-DNA相互作用.
- 凝聚蛋白复合体需要访问核细胞DNA才能进行染色体分离.
- 染色体重塑因子可以提高DNA的可访问性.
研究的目的:
- 为了分离和描述人类染色体重塑复合物的特征.
- 为了研究凝聚素复合物和染色质重塑剂之间的相互作用.
- 阐明这个复合体在DNA可访问性和调节中的作用.
主要方法:
- 隔离一个含有人类ISWI (SNF2h) 的复合体.
- 共同免疫沉以研究蛋白质相互作用 (hRAD21-SNF2h).
- 染色体免疫沉用于绘制 Alu 序列上的结合位点 (hRAD21,SNF2h,Mi2).
- 分析基因组尾变化和DNA甲基化效应.
主要成果:
- 一个包含SNF2h,cohesin (hRAD21) 和NuRD组件的新型综合体被分离出来.
- 证实了hRAD21和SNF2h之间的直接相互作用.
- SNF2h,hRAD21和Mi2特别与含有Alu序列的人类DNA元素结合.
- 基因组尾部修饰和DNA甲基化与SNF2h/凝聚素复合体与染色质相关.
- 有证据表明,SNF2h ATPase活性参与了将hRAD21加载到染色质上.
结论:
- 一种新型的SNF2h/凝聚素复合体在染色质可访问性方面发挥着作用.
- 这种复合体参与调节由表观遗传修饰影响的与染色质的凝聚性关联.
- SNF2h ATPase活性对hRAD21染色体负载至关重要,影响DNA-蛋白相互作用和染色体分离.
相关概念视频
02:54Nucleosome Remodeling
Nucleosomes are the basic units of chromatin compaction. Each nucleosome consists of the DNA bound tightly around a histone core, which makes the DNA inaccessible to DNA binding proteins such as DNA polymerase and RNA polymerase. Hence, the fundamental problem is to ensure access to DNA when appropriate, despite the compact and protective chromatin structure.
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
02:20Cohesins
Cohesin protein complexes are a molecular glue that holds two sister chromatids together. They play an important role both in mitosis and meiosis. In mitosis, all cohesin complexes present on the chromosomes are removed before the start of the anaphase stage.
Cohesin complexes in Meiotic Division
Meiosis involves two distinct rounds of chromosomal segregation and cell divisions— Meiosis I followed by Meiosis II – producing four daughter cells. Meiosis I includes the separation of homologous...
Cohesin complexes in Meiotic Division
Meiosis involves two distinct rounds of chromosomal segregation and cell divisions— Meiosis I followed by Meiosis II – producing four daughter cells. Meiosis I includes the separation of homologous...
02:15Condensins
Condensins are large protein complexes that use ATP to fuel the assembly of chromosomes during mitosis. They transform the tangled, shapeless mass of post-interphase DNA into individualized chromosomes by compacting, organizing, and segregating chromosomal DNA.
The plant and animal cells contain two types of condensin complexes—condensin I and condensin II. Both complexes have five subunits: two SMC (Structural Maintenance of Chromosomes) subunits, a kleisin subunit, and two HEAT-repeat...
The plant and animal cells contain two types of condensin complexes—condensin I and condensin II. Both complexes have five subunits: two SMC (Structural Maintenance of Chromosomes) subunits, a kleisin subunit, and two HEAT-repeat...
02:38Heterochromatin
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...
02:20Cohesins
Cohesin protein complexes are a molecular glue that holds two sister chromatids together. They play an important role both in mitosis and meiosis. In mitosis, all cohesin complexes present on the chromosomes are removed before the start of the anaphase stage.
Cohesin complexes in Meiotic Division
Meiosis involves two distinct rounds of chromosomal segregation and cell divisions— Meiosis I followed by Meiosis II – producing four daughter cells. Meiosis I includes the separation of homologous...
Cohesin complexes in Meiotic Division
Meiosis involves two distinct rounds of chromosomal segregation and cell divisions— Meiosis I followed by Meiosis II – producing four daughter cells. Meiosis I includes the separation of homologous...
02:15Condensins
Condensins are large protein complexes that use ATP to fuel the assembly of chromosomes during mitosis. They transform the tangled, shapeless mass of post-interphase DNA into individualized chromosomes by compacting, organizing, and segregating chromosomal DNA.
The plant and animal cells contain two types of condensin complexes—condensin I and condensin II. Both complexes have five subunits: two SMC (Structural Maintenance of Chromosomes) subunits, a kleisin subunit, and two HEAT-repeat...
The plant and animal cells contain two types of condensin complexes—condensin I and condensin II. Both complexes have five subunits: two SMC (Structural Maintenance of Chromosomes) subunits, a kleisin subunit, and two HEAT-repeat...