MCRS1 modulates the heterogeneity of microtubule minus-end morphologies in mitotic spindles.
Mol Biol Cell
; 34(1): ar1, 2023 01 01.
Article
in En
| MEDLINE
| ID: mdl-36350698
ABSTRACT
Faithful chromosome segregation requires the assembly of a bipolar spindle, consisting of two antiparallel microtubule (MT) arrays having most of their minus ends focused at the spindle poles and their plus ends overlapping in the spindle midzone. Spindle assembly, chromosome alignment, and segregation require highly dynamic MTs. The plus ends of MTs have been extensively investigated but their minus-end structure remains poorly characterized. Here, we used large-scale electron tomography to study the morphology of the MT minus ends in three dimensionally reconstructed metaphase spindles in HeLa cells. In contrast to the homogeneous open morphology of the MT plus ends at the kinetochores, we found that MT minus ends are heterogeneous, showing either open or closed morphologies. Silencing the minus end-specific stabilizer, MCRS1 increased the proportion of open MT minus ends. Altogether, these data suggest a correlation between the morphology and the dynamic state of the MT ends. Taking this heterogeneity of the MT minus-end morphologies into account, our work indicates an unsynchronized behavior of MTs at the spindle poles, thus laying the groundwork for further studies on the complexity of MT dynamics regulation.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Kinesins
/
Spindle Apparatus
Limits:
Humans
Language:
En
Journal:
Mol Biol Cell
Journal subject:
BIOLOGIA MOLECULAR
Year:
2023
Document type:
Article
Affiliation country:
Spain