Light-induced spindle assembly through Aurora A clustering.

Animal cells assemble gigadalton-scale molecular complexes composed of ~200 proteins to build a functional centrosome during mitosis, ensuring faithful chromosome segregation. Although the molecular principles underlying centrosome assembly have been extensively studied, the minimal components required to reconstitute centrosome-like activity in living cells remain unknown. Here, we develop an optogenetic strategy that exploits Aurora A kinase clustering to assemble functional centrosome-like structures in human cells. Remarkably, these light-induced assemblies activate Aurora A, nucleate microtubules, and bypass the requirement for the canonical Aurora A scaffold Cep192. Mechanistically, we identify the evolutionarily conserved Aurora A partner TPX2 as an essential factor for Aurora A cluster-dependent microtubule nucleation. Furthermore, optogenetic Aurora A clustering significantly rescues spindle assembly defects associated with centrosome ablation. We term this approach Light-Induced Spindle Assembly (LISA). By directly coupling Aurora A activity to spatial clustering, LISA defines a minimal and tunable module capable of driving spindle assembly. More broadly, LISA provides a synthetic biology platform for dissecting the fundamental principles of Aurora A-dependent spindle assembly, a prominent feature of mitotic and meiotic spindle formation.