The proteasome promotes cytokinetic abscission by relieving an Aurora B-dependent inhibition of ESCRT-III dynamics.

Proteasome activity is essential for cytokinetic abscission by degrading Aurora B, enabling ESCRT-III dynamics and membrane scission in human cells.

• Why it matters: Understanding how cell division concludes is vital, as errors can lead to diseases like cancer. The specific role of the proteasome in abscission was previously unclear, representing a gap in cell biology knowledge.
• What they did: The study inhibited the proteasome in human cells after furrow ingression and observed increased Aurora B levels, delayed microtubule severing, and impaired ESCRT-III polymer dynamics, with rescue experiments confirming Aurora B’s role.
• The result: Findings demonstrate that the proteasome promotes abscission by degrading Aurora B, reducing its activity, and thus facilitating ESCRT-III function, which advances understanding of the molecular mechanisms of cell division completion.