在Saccharomyces cerevisiae中的姐妹染色体凝聚力中,原产地识别复杂的功能
Kenji Shimada1, Susan M Gasser
1Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland.
Cell
|January 16, 2007
概括
原始识别复合体 (ORC) 蛋白质Orc2对于在细胞分裂过程中保持姐妹染色体凝聚力至关重要. Orc2的枯竭会损害凝聚力,突出了ORC在DNA复制之外的染色体分离中的新角色.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 高保真性染色体分离取决于及时的姐妹染色体凝聚力,主要由凝聚素复合体介导.
- 凝聚素的分辨率在基相-亚相过渡时对于精确的细胞分裂至关重要.
研究的目的:
- 研究起源识别复合体 (ORC) 蛋白Orc2在细胞循环进展和姐妹染色体凝聚力中的作用.
- 为了确定Orc2是否影响凝聚力,独立于Cohesin复合体与染色质的关联.
主要方法:
- 在预复制复合组合后,酵母菌株中Orc2的耗尽.
- 细胞循环进展,DNA损伤和螺杆检查点的分析.
- 评估姐妹染色体凝聚力和凝聚素子单元局部化.
- 重新表达Orc2和有针对性的本地化研究.
主要成果:
- 由于DNA损伤和螺杆检查点激活,Orc2耗尽延迟了线粒分裂.
- 姐妹染色体凝聚力在Orc2枯竭的细胞中受损,尽管Cohesin协会正常.
- Orc2的重新表达恢复了染色体凝聚力.
- 将Orc2定位在特定的位置上抑制了凝聚性突变体中过早分离的姐妹染色体.
结论:
- 原始识别复合体 (ORC) 在建立和维持姐妹染色体凝聚力方面发挥着重要作用.
- 通过ORC介导的凝聚作用于Cohesin介导配对的路径添加剂.
- 通过其在姐妹染色体凝聚力中的作用,Orc2对于适当的染色体分离至关重要.
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...
02:57Attachment 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...
02:17Separation of Sister Chromatids
At the transition from prophase to metaphase, there is a reduction in cohesion along the chromosomal arms, resulting in the resolution of sister chromatids. However, residual cohesin connections remain to hold the sister chromatids together until the transition from metaphase to anaphase. The residual connection prevents any premature separation of sister chromatids, blocking the risks of aneuploidy within the daughter cells.
At the onset of anaphase, separase, a proteolytic enzyme, is...
At the onset of anaphase, separase, a proteolytic enzyme, is...
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...
02:17Separation of Sister Chromatids
At the transition from prophase to metaphase, there is a reduction in cohesion along the chromosomal arms, resulting in the resolution of sister chromatids. However, residual cohesin connections remain to hold the sister chromatids together until the transition from metaphase to anaphase. The residual connection prevents any premature separation of sister chromatids, blocking the risks of aneuploidy within the daughter cells.
At the onset of anaphase, separase, a proteolytic enzyme, is...
At the onset of anaphase, separase, a proteolytic enzyme, is...