Video Experimental Relacionado
Updated: Jun 12, 2025

10:52
Reconstitution of Basic Mitotic Spindles in Spherical Emulsion Droplets
Published on: August 13, 2016
9.7K
Las cuentas cinetocoras artificiales establecen un estado similar a la biorientación en el husillo
Kohei Asai1,2, Yuanzhuo Zhou1,2, Osamu Takenouchi1
1Laboratory for Chromosome Segregation, RIKEN Center for Biosystems Dynamics Research (BDR), Kobe, Japan.
Resumen
Los investigadores crearon un cinetocore sintético utilizando el complejo NDC80-NUF2, lo que permite a las microesferas lograr la biorientación y alinearse en la célula
Área de la Ciencia:
- Biología celular
- Biología molecular
- La biofísica
Sus antecedentes:
- La segregación cromosómica fiel depende de la biorientación, donde los cinetocoros se unen a los microtúbulos del huso de los polos opuestos.
- Los componentes moleculares del cinetocoro son cruciales para este proceso, pero los elementos suficientes para la biorientación no están completamente identificados.
Objetivo del estudio:
- Investigar si los componentes específicos de los cinetocoros pueden inducir la biorientación en un sistema sintético.
- Determinar los componentes mínimos necesarios para establecer un estado similar a la biorientación.
Principales métodos:
- Enlazar el heterodímero cinetocoro externo NDC80-NUF2 con las microesferas apolares.
- Observando el comportamiento de estas microesferas biohíbridas en células de ratón usando microscopía.
- Analizando la fijación de los microtúbulos y la dinámica de alineación.
Principales resultados:
- Las microperlas NDC80-NUF2 lograron con éxito un estado similar a la biorientación, alineándose en el ecuador del husillo.
- Estas microperlas exhibieron una fijación de microtúbulos bipolar estable y errores de alineación autocorregidos.
- La alineación fue independiente de otras proteínas cinetocoras conocidas, lo que sugiere que NDC80-NUF2 es suficiente.
Conclusiones:
- El heterodímero NDC80-NUF2 es suficiente para impulsar la biorientación sintética de las partículas a microescala.
- Este estudio presenta un nuevo diseño de cinetocoros biohíbridos para la creación de sistemas de biorientación artificial.
- Los hallazgos avanzan en la comprensión de la función cinetocórica y los mecanismos de segregación cromosómica.
Videos de Conceptos Relacionados
Attachment of Sister Chromatids
3.2K
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...
3.2K
Forces Acting on Chromosomes
3.3K
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...
3.3K
Spindle Assembly
3.6K
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...
3.6K
The Spindle Assembly Checkpoint
3.1K
The spindle assembly checkpoint is a molecular surveillance mechanism ensuring the fidelity of chromosome segregation during anaphase. The checkpoint monitors the completion of all the prerequisite steps before chromosome segregation to determine whether the segregation process should proceed or be delayed.
Many proteins function together to control the spindle assembly checkpoint. Mutations affecting these proteins may allow cells to proceed into anaphase prematurely, resulting in the...
Many proteins function together to control the spindle assembly checkpoint. Mutations affecting these proteins may allow cells to proceed into anaphase prematurely, resulting in the...
3.1K
The Mitotic Spindle
6.5K
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...
6.5K
Anaphase A and B
4.0K
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...
4.0K

