Microtubule pushing and cortical pulling cooperate to orient and position the mitotic spindle.

Microtubule pushing forces are essential for preventing spindle stalling, enhancing robustness, and facilitating alignment alongside cortical pulling in diverse cell types.

• Why it matters: Understanding how spindle positioning and orientation are regulated is crucial for insights into cell division accuracy and tissue organization, yet the specific role of microtubule pushing forces remains unclear.
• What they did: A two-dimensional computational model incorporating both cortical pulling and microtubule pushing was developed and tested across various cell types and geometries, including spherical and irregular shapes.
• The result: The model shows pulling forces dominate spindle orientation, while pushing forces support stability and efficiency, and asymmetric force distributions can explain off-center spindle positioning in complex geometries.