Reduction of cortical pulling at mitotic entry facilitates aster centration.
J Cell Sci
; 137(7)2024 04 01.
Article
en En
| MEDLINE
| ID: mdl-38469748
ABSTRACT
Equal cell division relies upon astral microtubule-based centering mechanisms, yet how the interplay between mitotic entry, cortical force generation and long astral microtubules leads to symmetric cell division is not resolved. We report that a cortically located sperm aster displaying long astral microtubules that penetrate the whole zygote does not undergo centration until mitotic entry. At mitotic entry, we find that microtubule-based cortical pulling is lost. Quantitative measurements of cortical pulling and cytoplasmic pulling together with physical simulations suggested that a wavelike loss of cortical pulling at mitotic entry leads to aster centration based on cytoplasmic pulling. Cortical actin is lost from the cortex at mitotic entry coincident with a fall in cortical tension from â¼300pN/µm to â¼100pN/µm. Following the loss of cortical force generators at mitotic entry, long microtubule-based cytoplasmic pulling is sufficient to displace the aster towards the cell center. These data reveal how mitotic aster centration is coordinated with mitotic entry in chordate zygotes.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Semen
/
Huso Acromático
Límite:
Humans
/
Male
Idioma:
En
Revista:
J Cell Sci
/
J. cell. sci
/
Journal of cell science
Año:
2024
Tipo del documento:
Article
País de afiliación:
Francia