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Accurate regulation of centrosome size is essential for ensuring error-free cell division, and dysregulation of centrosome size has been linked to various pathologies, including developmental defects and cancer. While a universally accepted model for centrosome size regulation is lacking, prior theoretical and experimental works suggest a centrosome growth model involving autocatalytic assembly of the pericentriolar material. Here, we show that the autocatalytic assembly model fails to explain the attainment of equal centrosome sizes, which is crucial for error-free cell division. Incorporating latest experimental findings into the molecular mechanisms governing centrosome assembly, we introduce a new quantitative theory for centrosome growth involving catalytic assembly within a shared pool of enzymes. Our model successfully achieves robust size equality between maturing centrosome pairs, mirroring cooperative growth dynamics observed in experiments. To validate our theoretical predictions, we compare them with available experimental data and demonstrate the broad applicability of the catalytic growth model across different organisms, which exhibit distinct growth dynamics and size scaling characteristics.
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This content will become publicly available on January 3, 2026
Ipsilateral restriction of chromosome movement along a centrosome, and apical- basal axis during the cell cycle
Little is known about how distance between homologous chromosomes are controlled during the cell cycle. Here, we show that the distribution of centromere components display two discrete clusters placed to either side of the centrosome and apical/basal axis from prophase to G1 interphase. 4- Dimensional live cell imaging analysis of centromere and centrosome tracking reveals that centromeres oscillate largely within one cluster, but do not cross over to the other cluster. We propose a model of an axis-dependent ipsilateral restriction of chromosome oscillations throughout mitosis.
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- Award ID(s):
- 2027746
- PAR ID:
- 10559616
- Editor(s):
- Sullivan, Beth A
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Chromosome research
- ISSN:
- 0967-3849
- Subject(s) / Keyword(s):
- homologous chromosomes, chromosomes, mitosis, cell cycle, centromeres
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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