对于建立姐妹染色体凝聚力的分子决定因素
Elçin Unal1, Jill M Heidinger-Pauli, Woong Kim
1Howard Hughes Medical Institute and Department of Embryology, Carnegie Institution, 3520 San Martin Drive, Baltimore, MD 21218, USA.
Science (New York, N.Y.)
|July 26, 2008
概括
科学家们发现了凝聚蛋白质复合体是如何建立姐妹染色体凝聚力的. 在S阶段由Eco1p对Smc3p亚单元的乙化是染色体结合的关键,揭示了细胞周期调节的洞察力.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 遗传学 遗传学 是一个
背景情况:
- 凝聚蛋白复合体对于染色体分离,DNA修复和转录调节至关重要.
- 凝聚素的主要作用是保持姐妹染色体凝聚力,但其建立的机制仍然不清楚.
- 了解凝聚蛋白功能对于理解基因组稳定性和细胞分裂至关重要.
研究的目的:
- 阐明凝聚复合体建立姐妹染色体凝聚力的机制.
- 确定关键的分子事件和参与凝聚力建立的监管因素.
- 为了研究后翻译性修改在凝聚功能中的作用.
主要方法:
- 利用芽生长酵母 (Saccharomyces cerevisiae) 作为一个模型生物体.
- 研究了凝聚素复合物的Smc3p亚单元的乙化.
- 研究了与Smc3p相关的Eco1p乙转移酶的酶活性.
- 分析了Smc3p乙化的细胞周期特异调节.
主要成果:
- 通过Eco1p在保存残留物中识别了Smc3p子单元的头域的乙化.
- 证明Smc3p乙化促进了通过染色质结合凝聚素的姐妹染色体的结合.
- 表明Smc3p乙化在S阶段被特别诱导,并在G1和G2/M阶段被抑制.
- 确立了Smc3p乙化与细胞周期依赖的凝聚素负载和功能之间的联系.
结论:
- Smc3p头化是建立姐妹染色体凝聚力的关键步骤.
- 通过Eco1p对Smc3p的细胞循环调节的乙化提供了一个控制DNA复制过程中凝聚蛋白功能的机制.
- 这些发现为基础凝聚力建立的基本生物学和分子机制提供了重要的见解.
相关概念视频
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...
02:20Cohesins
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...
02:57Attachment of Sister Chromatids
As cells progress into mitosis, the nuclear envelope breaks down, and the condensed chromosomes are exposed to the array of bipolar microtubules of the mitotic spindle. The kinetochore, a large, disc-shaped protein complex, is present at the centromere region of the sister chromatids and acts as a binding site for the microtubules. Usually, the plus-end of a single microtubule is embedded within the kinetochore. However, some kinetochores first establish lateral contact with the side-wall of a...
02:57Attachment of Sister Chromatids
As cells progress into mitosis, the nuclear envelope breaks down, and the condensed chromosomes are exposed to the array of bipolar microtubules of the mitotic spindle. The kinetochore, a large, disc-shaped protein complex, is present at the centromere region of the sister chromatids and acts as a binding site for the microtubules. Usually, the plus-end of a single microtubule is embedded within the kinetochore. However, some kinetochores first establish lateral contact with the side-wall of a...
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...
02:15Condensins
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...