染色体凝聚和解凝聚的焦点通过三维in vivo时间缩短显微镜揭示
Y Hiraoka1, J S Minden, J R Swedlow
1Department of Biochemistry and Biophysics, University of California, San Francisco 94143-0448.
Nature
|November 16, 1989
概括
染色体在特定的核外区域解密和凝结,而不仅仅是中心分子或端粒. 这些位点指导细胞周期中的染色体组织,揭示了对核动力学的新见解.
科学领域:
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
- 显微镜的使用方法
背景情况:
- 染色体动力学在线粒分裂过程中得到了很好的研究,但在介相过程中对染色体动力学知之甚少.
- 以前的研究表明,在核外围发生非均的染色体凝聚.
研究的目的:
- 记录染色体在过渡到和从相间转变期间的行为.
- 了解活体组织中染色体凝聚和脱凝的动态过程.
主要方法:
- 使用了先进的三维时隔光显微镜.
- 通过新的立体投影和计算处理改进了图像分辨率.
主要成果:
- 观察到染色体从telophase通过interphase到prophase凝结时进行脱凝.
- 在核外上确定了特定的染色体区域,不包括中间体和端粒,作为脱凝/凝聚焦点.
- 发现晚期脱凝点与随后的预相中的早期凝结点相关.
结论:
- 特定的核外区域在相间期间起到染色体组织的关键作用.
- 这一发现为染色体动力学和整个细胞周期的核架构提供了新的视角.
相关概念视频
Chromosome Structure
A functional eukaryotic chromosome must contain three elements: a centromere, telomeres, and numerous origins of replication.
The centromere is a DNA sequence that links sister chromatids. This is also where kinetochores, protein complexes to which spindle microtubules attach, are constructed after the chromosome is replicated. The kinetochores allow the spindle microtubules to move the chromosomes within the cell during cell division.
Telomeres consist of non-coding repetitive nucleotide...
The centromere is a DNA sequence that links sister chromatids. This is also where kinetochores, protein complexes to which spindle microtubules attach, are constructed after the chromosome is replicated. The kinetochores allow the spindle microtubules to move the chromosomes within the cell during cell division.
Telomeres consist of non-coding repetitive nucleotide...
Polytene Chromosomes
Polytene chromosomes are giant interphase chromosomes with several DNA strands placed side by side. They were discovered in the year 1881 by Balbiani in salivary glands, intestine, muscles, malpighian tubules, and hypoderm of larvae Chironomus plumosus. Hence, these are also called "Salivary gland chromosomes." These are found in insects of the order Diptera and Collembola; in certain organs of mammals; and synergids, antipodes of flowering plants. Polytene chromosomes are also regularly...
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...
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...
Forces Acting on Chromosomes
During mitosis, chromosome movements occur through the interplay of multiple piconewton level forces. In prometaphase, these forces help in chromosome assembly or congression at the equatorial plane, eventually leading to their alignment at the metaphase plate. The forces acting on the chromosomes are space and time-dependent; therefore, they vary with the position of the chromosomes as the cell progresses through mitosis.
Microtubules and motor proteins exert two types of forces on...
Microtubules and motor proteins exert two types of forces on...


