齐亚梅斯 (Zea mays) 梅奥斯螺旋超结构揭示了基内托科尔-微管网接口和嵌入膜组件
Subin Myong1, Jenna K Cosby1, Brianna N Padilla1
1Department of Biology, Hamilton College, Clinton, New York, USA.
Cytogenetic and genome research
|July 29, 2025
概括
这项研究揭示了Zea mays介质的3D结构,识别了植物特有的特征,如内部膜通道和独特的微管环,这对染色体分离至关重要.
科学领域:
- 细胞生物学 细胞生物学
- 细胞遗传学 细胞遗传学
- 结构生物学 结构生物学
背景情况:
- 细胞分裂依赖于螺旋装置来准确分离染色体.
- 螺旋结构至关重要;错误会导致形,疾病和不孕症.
- 齐亚梅斯 (Zea mays) 是一个重要的作物和模型系统,但其中介螺旋结构仍然没有特征.
研究的目的:
- 为了在纳米分辨率下阐明Zea mays的三维超结构的介质螺旋.
- 识别和描述玉米介质的关键组件和独特特征.
- 为了与其他生物体的玉米结构进行比较.
主要方法:
- 电子断层扫描 (ET) 用于捕捉玉米中介线轴的高分辨率3D图像.
- 重建和建模技术被用来可视化微管,kinetochores和相关结构.
- 免疫覆盖和活光显微镜证实了模拟的结构.
主要成果:
- 玉米中介螺旋具有8-18个kinetochore微管 (kMTs) 每个kinetochore.
- 观察到的独特结构包括小型囊泡 (~37 nm) 和大型膜通道 (~5 μm长,800 nm宽) 含有微管,对ER标志物呈阳性.
- 确定了一种具有交叉口排列的周核微管环和具有跨核微管的核沟.
结论:
- 齐亚梅斯的介质与动物有相似之处,包括kMT数和跨核微管.
- 植物特有的特征包括Golgi衍生的囊泡用于细胞板形成和内部ER膜通道.
- 周核微管环有助于螺杆组装,玉米动态细胞表现出明显的"球在杯子"形态.
相关概念视频
02:27The Mitotic Spindle
6.8K
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...
The bipolar configuration of the mitotic spindle facilitates chromosomal segregation, preparing the cell for division. One mechanism that ensures...
6.8K
02:50Spindle Assembly
3.8K
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...
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...
3.8K
01:57Meiosis II
184.4K
Meiosis II is the second and final stage of meiosis. It relies on the haploid cells produced during meiosis I, each of which contain only 23 chromosomes—one from each homologous initial pair. Importantly, each chromosome in these cells is composed of two joined copies, and when these cells enter meiosis II, the goal is to separate such sister chromatids using the same microtubule-based network employed in other division processes. The result of meiosis II is two haploid cells, each...
184.4K
02:57Meiosis vs. Mitosis
58.2K
Cell division is necessary for growth and reproduction in organisms. Mitosis aids cell growth and development by dividing somatic cells. In contrast, meiosis causes the division of germ cells and plays an essential role in sexual reproduction. Due to their unique functional requirements, mitosis and meiosis differ from each other in multiple aspects.
Before the start of mitosis and meiosis I, the cell synthesizes DNA, resulting in two homologous copies of each chromosome. DNA synthesis is...
Before the start of mitosis and meiosis I, the cell synthesizes DNA, resulting in two homologous copies of each chromosome. DNA synthesis is...
58.2K
01:49Meiosis I
194.6K
Meiosis is a carefully orchestrated set of cell divisions, the goal of which—in humans—is to produce haploid sperm or eggs, each containing half the number of chromosomes present in somatic cells elsewhere in the body. Meiosis I is the first such division, and involves several key steps, among them: condensation of replicated chromosomes in diploid cells; the pairing of homologous chromosomes and their exchange of information; and finally, the separation of homologous chromosomes by...
194.6K
01:39Anaphase A and B
4.2K
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...
4.2K