@article{mahoney_needham_hakeem_begley_medina_elting_2026, title={Spindle biochemistry responds to compressive force from the nuclear envelope to tune spindle dynamics during closed mitosis}, volume={1}, url={http://dx.doi.org/10.64898/2026.01.15.699759}, DOI={10.64898/2026.01.15.699759}, abstractNote={During closed mitosis in <i>S. pombe</i> , the nuclear envelope and mitotic spindle must work together mechanically and biochemically to ensure successful nuclear division. Previous work has demonstrated that mechanical force from the nuclear envelope, transmitted through spindle pole bodies, can re-shape the spindle. However, it remains unclear how force might alter spindle biochemistry. Here, we investigate how force reprograms the spindle with two approaches: chronically increasing nuclear envelope tension via the lipid synthesis inhibitor cerulenin, and acutely applying force through an optical trap. Both perturbations slow elongation dynamics and reduce microtubule number. Despite this reduction, key spindle proteins Ase1 and Klp5 increase their density at the spindle midzone, indicating inward force from the nuclear envelope can alter spindle biochemistry. We find that while motor proteins Klp5 and Klp6 only minimally affect the spindle's response to increased nuclear envelope force, the combination of removing Ase1 and increasing nuclear envelope force together rescue spindle stability. Together, our findings reveal that nuclear force on the spindle does not merely alter its shape, but is key in regulating its biochemistry to maintain force balance.}, author={Mahoney, Taylor and Needham, Christopher and Hakeem, Reem and Begley, Marcus and Medina, Christian Pagán and Elting, Mary Williard}, year={2026}, month={Jan} }
 @article{begley_mahoney_medina_zareiesfandabadi_rapp_tirfe_leblanc_betterton_elting_2025, title={Mechanical Coupling With the Nuclear Envelope Shapes the <i>Schizosaccharomyces pombe</i> Mitotic Spindle}, volume={5}, DOI={10.1002/cm.22035}, abstractNote={ABSTRACT The fission yeast Schizosaccharomyces pombe divides via closed mitosis, meaning that spindle elongation and chromosome segregation transpire entirely within the closed nuclear envelope. Both the spindle and nuclear envelope must undergo shape changes and exert varying forces on each other during this process. Previous work has demonstrated that nuclear envelope expansion (Yam, He, Zhang, Chiam, & Oliferenko, 2011; Mori & Oliferenko, 2020) and spindle pole body (SPB) embedding in the nuclear envelope are required for normal S. pombe mitosis, and mechanical modeling has described potential contributions of the spindle to nuclear morphology (Fang et al., 2020; Zhu et al., 2016). However, it is not yet fully clear how and to what extent the nuclear envelope and mitotic spindle each directly shape each other during closed mitosis. Here, we investigate this relationship by observing the behaviors of spindles and nuclei in live mitotic fission yeast following laser ablation. First, we characterize these dynamics in mitotic S. pombe nuclei with increased envelope tension, finding that nuclear envelope tension can both bend the spindle and slow elongation. Next, we directly probe the mechanical connection between spindles and nuclear envelopes by ablating each structure. We demonstrate that envelope tension can be relieved by severing spindles and that spindle compression can be relieved by rupturing the envelope. We interpret our experimental data via two quantitative models that demonstrate that fission yeast spindles and nuclear envelopes are a mechanical pair that can each shape the other's morphology.}, journal={Cytoskeleton}, author={Begley, Marcus A. and Mahoney, Taylor and Medina, Christian Pagán and Zareiesfandabadi, Parsa and Rapp, Matthew B. and Tirfe, Mastawal and LeBlanc, Sharonda J. and Betterton, Meredith D. and Elting, Mary Williard}, year={2025}, month={May} }