皮层dynein和不对称的膜延长坐标地将螺旋置于无相阶段
Tomomi Kiyomitsu1, Iain M Cheeseman
1Whitehead Institute for Biomedical Research, Nine Cambridge Center, Cambridge, MA 02142, USA. tomomi.kiyomitsu@gmail.com
Cell
|July 23, 2013
概括
在人类细胞分裂过程中,有两种机制协调了轴心的定位. 迪内因运动蛋白和不对称的膜延长通过将线粒螺旋置于中心,确保相同尺寸的子细胞.
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:
- 线粒体的定位对于细胞动力学和产生平等的子细胞至关重要.
- 控制对称细胞分裂的螺旋定位的机制尚未完全理解.
研究的目的:
- 在对称地分裂的人类细胞中,阐明在亚纳相期间轴心中心化的机制.
- 为了确定调节dynein向和细胞皮层相互作用的途径.
主要方法:
- 在螺旋定位中研究了dynein运动蛋白的功能.
- 利用遗传和细胞生物学方法研究蛋白质定位和功能.
- 在细胞分裂过程中分析细胞形态和膜动力学.
主要成果:
- 确定了两条向细胞皮质的dynein的途径:一种依赖Gαi/LGN/NuMA的途径和一种特定于亚纳的4.1G/R和NuMA的途径.
- 证明了不对称的血延长发生在响应错位时.
- 表明Ran-GTP信号通过减少Anillin来调节不对称的膜延长.
- 在延长细胞中的静止皮质上确认了dynein依赖的螺旋.
结论:
- 两个协调的机制确保正确的螺旋定位,以实现相同的细胞分裂.
- 迪内因运动活性和受调节的膜延长是对称细胞运动的关键.
- 特定于相的通路有助于精确的轴中心.
相关概念视频
Spindle Assembly
Spindle assembly occurs through three, often coexisting, pathways – the centrosome-mediated pathway, the chromatin-mediated pathway, and the microtubule-mediated pathway – collectively contributing to form a robust spindle apparatus.
In most cells, centrosomes are the primary microtubule nucleation centers. In the centrosome-mediated pathway, the G2-prophase transition triggers centrosome maturation and increased microtubule nucleation. Progressive nucleation results in a microtubule array...
In most cells, centrosomes are the primary microtubule nucleation centers. In the centrosome-mediated pathway, the G2-prophase transition triggers centrosome maturation and increased microtubule nucleation. Progressive nucleation results in a microtubule array...
Anaphase A and B
Microtubules form through the end-to-end polymerization of tubulin heterodimers. Kinetochore microtubules originate from the spindle poles, and their plus-ends connect with the kinetochores on sister-chromatids. Ndc80 protein complexes, present on the kinetochore, form low-affinity links with the plus end of these kinetochore microtubules.
Plus-end depolymerization releases tubulin heterodimers from the terminal region of the microtubule. As tubulin subunits are lost, the Ndc80 complexes detach...
Plus-end depolymerization releases tubulin heterodimers from the terminal region of the microtubule. As tubulin subunits are lost, the Ndc80 complexes detach...
Anaphase A and B
Microtubules form through the end-to-end polymerization of tubulin heterodimers. Kinetochore microtubules originate from the spindle poles, and their plus-ends connect with the kinetochores on sister-chromatids. Ndc80 protein complexes, present on the kinetochore, form low-affinity links with the plus end of these kinetochore microtubules.
Plus-end depolymerization releases tubulin heterodimers from the terminal region of the microtubule. As tubulin subunits are lost, the Ndc80 complexes detach...
Plus-end depolymerization releases tubulin heterodimers from the terminal region of the microtubule. As tubulin subunits are lost, the Ndc80 complexes detach...
The Mitotic Spindle
The mitotic spindle—or spindle apparatus—is a eukaryotic, cytoskeletal structure made up of long protein fibers called microtubules. Formed during cell division, the spindle separates sister chromatids and moves them to opposite ends of a parental cell, where the now individual chromosomes are distributed to two daughter cell nuclei.
The bipolar configuration of the mitotic spindle facilitates chromosomal segregation, preparing the cell for division. One mechanism that ensures bipolar mitotic...
The bipolar configuration of the mitotic spindle facilitates chromosomal segregation, preparing the cell for division. One mechanism that ensures bipolar mitotic...
The Mitotic Spindle
The mitotic spindle—or spindle apparatus—is a eukaryotic, cytoskeletal structure made up of long protein fibers called microtubules. Formed during cell division, the spindle separates sister chromatids and moves them to opposite ends of a parental cell, where the now individual chromosomes are distributed to two daughter cell nuclei.
The bipolar configuration of the mitotic spindle facilitates chromosomal segregation, preparing the cell for division. One mechanism that ensures bipolar mitotic...
The bipolar configuration of the mitotic spindle facilitates chromosomal segregation, preparing the cell for division. One mechanism that ensures bipolar mitotic...
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...


