Kinetochores accelerate centrosome separation to ensure faithful chromosome segregation

التفاصيل البيبلوغرافية
العنوان: Kinetochores accelerate centrosome separation to ensure faithful chromosome segregation
المؤلفون: René Holtackers, Mukta Belwal, Samuel Wieser, Ana C. Amaro, Julien Mouysset, Nunu Mchedlishvili, Patrick Meraldi
المصدر: Journal of Cell Science, Vol. 125, No Pt 4 (2012) pp. 906-18
Journal of cell science
بيانات النشر: The Company of Biologists, 2012.
سنة النشر: 2012
مصطلحات موضوعية: Prometaphase, M Phase Cell Cycle Checkpoints, Chromosomal Proteins, Non-Histone, Nuclear Envelope, Cell Cycle Proteins, Spindle Apparatus, Biology, Microtubule-Associated Proteins/deficiency/metabolism, Microtubules, Chromosome segregation, 03 medical and health sciences, 0302 clinical medicine, Microtubule, Chromosome Segregation, Humans, Kinetochores, Mitosis, Nuclear Envelope/metabolism, 030304 developmental biology, Centrosome, 0303 health sciences, Kinetochore, Cell Biology, Cell biology, Cell Cycle Proteins/deficiency/metabolism, Centrosome/metabolism, Kinetochores/metabolism, Microtubules/metabolism, Centrosome separation, Microtubule-Associated Proteins, Mitotic Spindle Apparatus/metabolism, 030217 neurology & neurosurgery, HeLa Cells
الوصف: At the onset of mitosis, cells need to break down their nuclear envelope, form a bipolar spindle and attach the chromosomes to microtubules via kinetochores. Previous studies have shown that spindle bipolarization can occur either before or after nuclear envelope breakdown. In the latter case, early kinetochore–microtubule attachments generate pushing forces that accelerate centrosome separation. However, until now, the physiological relevance of this prometaphase kinetochore pushing force was unknown. We investigated the depletion phenotype of the kinetochore protein CENP-L, which we find to be essential for the stability of kinetochore microtubules, for a homogenous poleward microtubule flux rate and for the kinetochore pushing force. Loss of this force in prometaphase not only delays centrosome separation by 5–6 minutes, it also causes massive chromosome alignment and segregation defects due to the formation of syntelic and merotelic kinetochore–microtubule attachments. By contrast, CENP-L depletion has no impact on mitotic progression in cells that have already separated their centrosomes at nuclear envelope breakdown. We propose that the kinetochore pushing force is an essential safety mechanism that favors amphitelic attachments by ensuring that spindle bipolarization occurs before the formation of the majority of kinetochore–microtubule attachments.
تدمد: 1477-9137
0021-9533
الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f90b7f1bfc640f0226f7fc8e71237e7bTest
https://doi.org/10.1242/jcs.091967Test
حقوق: OPEN
رقم الانضمام: edsair.doi.dedup.....f90b7f1bfc640f0226f7fc8e71237e7b
قاعدة البيانات: OpenAIRE