试验室染色体组合:凝结过程中需要二氧化酶II
Y Adachi1, M Luke, U K Laemmli
1University of Geneva, Department of Biochemistry, Switzerland.
Cell
|January 11, 1991
概括
拓酶II (topo II) 对于染色体的凝聚是至关重要的. 耗尽topo II防止红细胞核凝结,突出其在这个重要的细胞过程中的结构性作用.
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:
- 染色体凝聚对于准确的细胞分裂至关重要.
- 拓酶II (topo II) 是一种涉及DNA管理的酶.
- 图波II在染色体凝聚中的确切作用仍在研究中.
研究的目的:
- 为了研究拓酶II (topo II) 在染色体凝聚中的作用.
- 为了确定Topo II是否在结构上是形成线粒染色体所必需的.
主要方法:
- 使用了从Xenopus蛋中提取的线粒提取物.
- 采用特异性免疫减弱来去除多聚酶II (TOPOII).
- 在HeLa和红细胞核中使用耗尽的提取物评估染色体凝结.
主要成果:
- HeLa 核通常在 topo II 枯竭的提取物中凝结,表明足够的内源酶.
- 的红细胞核未能凝结在II型乏的提取物中.
- 在的红细胞核中添加净化的TOPO II恢复凝结.
- 剂量实验表明Topo II在凝结中的结构作用.
- 枯竭的提取物导致了缺乏核结构的预冷凝染色体.
结论:
- 拓酶II (topo II) 在染色体凝聚过程中发挥着关键的,潜在的结构性作用.
- 酶的存在对于具有低内源水平的核形成线粒染色体至关重要.
相关概念视频
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Cohesins
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...
Condensins
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...
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