Tracing the dynamic recruitment trajectory of Optineurin between the centrosome and other macromolecular assemblies, signifying its role in cell cycle progression

The intricate recruitment trajectory of the protein Optineurin (OPTN) between the centrosome and other macromolecular assemblies sheds light on its essential role in cell cycle progression. The spatiotemporal allocation and dynamic redistribution of centrosomal proteins are vital for orchestrating the structural and molecular events required for successful cell division.

It was previously observed that OPTN is present at crucial cell-division assemblies, prompting the question of how its trafficking is orchestrated during cell division. By coupling cell-cycle synchronization with flow cytometric analysis and confocal microscopy, researchers found that OPTN progressively detaches from centrosomes during mitosis, moves to cytokinetic structures, accumulates at the spindle midzone, and finally concentrates at the midbody during cytokinesis.

Following this transition, OPTN reappears at centrosomes during G1 of the subsequent cell cycle. Additionally, experiments involving microtubule perturbation and regrowth assays suggest that OPTN recruitment and retention at the pericentriolar matrix (PCM) can occur independently of microtubules, while its exit is dependent on microtubules.

This study is the first to provide a detailed movement trail of OPTN, emphasizing its centrosome-linked redistribution and microtubule dependency. The context-dependent localization and trafficking of OPTN along the centrosome-midbody axis provide a comprehensive roadmap that can be strategically employed to investigate its functional role in cell division.