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arXiv · 2407.08899

Telomeres in Lamin-A Depleted Cells Exhibit Directed Motion and Dynamic Coherence

Abstract

Investigating the dynamics of chromatin loci and the factors that influence them provides valuable insights into the organization and functionality of the genome within the cell nucleus. We control the expression of Lamin-A, an important organizer of chromatin and nuclear structure. By simultaneously tracking hundreds of telomeres in Lamin-A knocked-out (KO) and wild-type (WT) nuclei, we find that telomere motion in Lamin-A depleted cells is both faster and more directed on micrometer scales, comparable to the size of chromosome territories. In contrast, telomere trajectories in WT cells exhibit pronounced anti-persistent behavior, consistent with caging by the surrounding chromatin environment. We further observe correlated motion between distinct telomeres in both WT and KO cells, with significantly stronger correlations in the KO case, indicating enhanced collective behavior. These correlations reflect cross-correlations among different loci rather than temporal correlations along individual trajectories. Together, these findings highlight the central role of Lamin-A in regulating both local confinement and collective telomere dynamics.

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M. Hidalgo-Soria, W. Nicola, Y. Haddad, E. Barkai, S. Burov, Y. Garini. 2026-06-24. Telomeres in Lamin-A Depleted Cells Exhibit Directed Motion and Dynamic Coherence. https://doi.org/10.1016/j.bpj.2026.05.021

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