biostudies-literatureUnknownOkafornta CWNIH HHSHow embryos adapt their internal cellular machinery to reductions in cell size during development remains a fundamental question in cell biology^1-11. Here, we use high-resolution lattice light-sheet fluorescence microscopy and automated image analysis to quantify lineage-resolved mitotic spindle and chromosome segregation dynamics from the 2- to 64-cell stages in <i>Caenorhabditis elegans</i> embryos. While spindle length scales with cell size across both wild-type and size-perturbed embryos, chromosome segregation dynamics remain largely invariant, suggesting that distinct mechanisms govern these mitotic processes. Combining femtosecond laser ablation^12,13 with large-scale electron tomography¹⁴, we find that central spindle microtubules mediate chromosome Research squarers.3.rs-7923379https://www.ebi.ac.uk/biostudies/studies/S-EPMC12687828biostudies-literatureCell size reduction scales spindle elongation but not chromosome segregation in &lt;i&gt;C. elegans&lt;/i&gt;.PMC12687828P40 OD010440Farhadifar ROkafornta CWMuller-Reichert TBaum DNeedleman DJKockert MFabig GWu HYVogel MHaase RShelley MJfalseCell size reduction scales spindle elongation but not chromosome segregation in &lt;i&gt;C. elegans&lt;/i&gt;.How embryos adapt their internal cellular machinery to reductions in cell size during development remains a fundamental question in cell biology^1-11. Here, we use high-resolution lattice light-sheet fluorescence microscopy and automated image analysis to quantify lineage-resolved mitotic spindle and chromosome segregation dynamics from the 2- to 64-cell stages in <i>Caenorhabditis elegans</i> embryos. While spindle length scales with cell size across both wild-type and size-perturbed embryos, chromosome segregation dynamics remain largely invariant, suggesting that distinct mechanisms govern these mitotic processes. Combining femtosecond laser ablation^12,13 with large-scale electron tomography¹⁴, we find that central spindle microtubules mediate chromosome 2025-01-01T00:00:00Z2025 Dec2026-06-04T03:21:18.695Z2026-06-04T03:12:44.147ZS-EPMC126878284137796410.21203/rs.3.rs-7923379/v1