Video Experimental Relacionado
Updated: Apr 11, 2026

10:01
Production of Xenopus tropicalis Egg Extracts to Identify Microtubule-associated RNAs
Published on: June 27, 2013
14.3K
Separación de microtúbulos estables por una proteína mitóticamente activada en extractos de huevo de Xenopus
1Department of Pharmacology, University of California, San Francisco 94143.
Cell
|February 22, 1991
Resumen
Los científicos descubrieron una proteína en los extractos de huevo de Xenopus que separa los microtúbulos. Esta actividad de corte de microtúbulos se mejora durante la mitosis, ayudando potencialmente en la reorganización del ciclo celular.
Área de la Ciencia:
- Biología celular Biología celular.
- Dinámica del citoesqueleto Dinámica del citoesqueleto
- Biología Molecular Biología Molecular
Sus antecedentes:
- Las células eucariotas remodelan dinámicamente su citoesqueleto para procesos esenciales como el ciclo celular.
- El desmontaje del filamento de actina se facilita al cortar las proteínas, pero tales factores para los microtúbulos eran desconocidos.
- Los microtúbulos son críticos para la estructura celular, la división y el transporte intracelular.
Objetivo del estudio:
- Identificar y caracterizar las proteínas responsables de la separación de microtúbulos en extractos de células eucariotas.
- Investigar la regulación de la actividad de corte de microtúbulos durante el ciclo celular, particularmente la mitosis.
Principales métodos:
- Extractos utilizados de huevos de Xenopus, conocidos por su utilidad en estudios del ciclo celular.
- Se analizó la actividad de corte de microtúbulos en extractos celulares.
- Investigó la regulación de esta actividad, incluidas las modificaciones post-traduccionales durante la mitosis.
Principales resultados:
- Identificaron una nueva actividad en los extractos de huevo de Xenopus que separa rápidamente los microtúbulos estables a lo largo de su longitud.
- Esta actividad de corte de microtúbulos se mejora significativamente durante la mitosis.
- La mejora de la actividad de corte está mediada por un mecanismo post-traducional.
Conclusiones:
- Un factor proteico de corte de microtúbulos existe en los extractos de huevo de Xenopus.
- La actividad de este factor está regulada, aumentando durante la mitosis.
- El factor de corte de microtúbulos identificado probablemente juega un papel en el desmontaje de la red de microtúbulos de interfase para la formación del huso mitótico.
Videos de Conceptos Relacionados
Destabilization of Microtubules
3.9K
The destabilization of microtubules can occur during different stages of the microtubule lifecycle, such as nucleation or elongation. It can take place at either end of the microtubule or in the microtubule lattices as a whole. The lifespan of individual microtubules within a cell varies according to the cell type and stage of the cell cycle. During interphase, the lifespan of the microtubule is about 30 minutes, while during cell division, it is about 15 minutes. In axonal microtubules of...
3.9K
Drugs that Stabilize Microtubules
2.9K
Microtubules are dynamic structures that undergo cycles of catastrophe and rescue. The microtubules play a central role in cell division by forming the spindle apparatus for segregating the chromosomes. This makes them ideal targets for regulating dividing cells in tumors and malignant cancer cells. Microtubule stabilizing drugs help stabilize the microtubule formation and promote its polymerization. Paclitaxel was the first microtubule stabilizing agent used as anticancer drug in chemotherapy...
2.9K
Microtubule Instability
6.5K
Microtubules are hollow cylindrical filaments having a diameter of approximately 25 nm and a length that varies from 200 nm to 25 μm. GTP-bound tubulin subunits form αβ-heterodimers for microtubule assembly. These core building blocks interact longitudinally, polymerizing into protofilaments. The protofilaments then interact with one another through lateral bonding forces to form stable cylindrical microtubules. These cylindrical filaments are dynamic as they undergo repeated...
6.5K
Spindle Assembly
4.5K
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...
4.5K
Anaphase A and B
5.8K
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...
5.8K
Drugs that Destabilize Microtubules
4.3K
Microtubules are dynamic structures and can be regulated by microtubule targeting agents (MTAs). Microtubule destabilizing drugs are a class of MTAs that destabilize and prevent microtubules' polymerization. Both natural and synthetic chemicals can be found under this class of drugs. Vincristine and vinblastine, two vinca alkaloids, and colchicine were among the first to be discovered. These drugs can affect cells in various ways, either by inducing a change in cell morphology, preventing...
4.3K

