2016/06/14 by Paolo Malgaretti, Sudipto Muhuri · 4 citations
Biochemistry, Genetics and Molecular Biology · Chemistry · Physics and Astronomy · #Biology #Biophysics #Bistability #Cell #Cell biology #Cell division #Cellular Mechanics and Interactions #Cellular transport and secretion #Centrosome #Chemistry #Chromosome #Kinetochore #Microtubule #Microtubule and mitosis dynamics #Mitosis #Motor protein #Physics #Spindle apparatus #Spindle pole body #cond-mat.soft #physics.bio-ph #q-bio.SC
paper · pdf · doi:10.1209/0295-5075/115/28001
published in Europhysics Letters (EPL) 115(2), 28001 (Institute of Physics) · 7 pages, 6 figures, under review in EPL
arxiv created 2016/06/14 · openalex publication_date 2016/07/01 · arxiv updated 2016/08/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Assembly and stability of mitotic spindle are governed by the interplay of various intra-cellular forces, e.g. the forces generated by motor proteins by sliding overlapping anti-parallel microtubules (MTs) polymerized from the opposite centrosomes, the interaction of kinetochores with MTs, and the interaction of MTs with the chromosome arms. We study the mechanical behavior and stability of spindle assembly within the framework of a minimal model which includes all these effects. For this model, we derive a closed-form analytical expression for the force acting between the centrosomes as a function of their separation distance and we show that an effective potential can be associated with the interactions at play. We obtain the stability diagram of spindle formation in terms of parameters characterizing the strength of motor sliding, repulsive forces generated by polymerizing MTs, and the forces arising out of the interaction of MTs with kinetochores. The stability diagram helps in quantifying the relative effects of the different interactions and elucidates the role of motor proteins in formation and inhibition of spindle structures during mitotic cell division. We also predict a regime of bistability for a certain parameter range, wherein the spindle structure can be stable for two different finite separation distances between centrosomes. This occurrence of bistability also suggests the mechanical versatility of such self-assembled spindle structures.