CONSERVED NUCLEAR MORPHOLOGY IDENTIFIES FUNCTIONAL RADIAL GLIA NEURAL PROGENITORS
Mechanical cues influence neural development, yet how tissue architecture is integrated into progenitor cell states remains poorly understood. Here, we show that defined microtopographies induce an early nuclear remodeling program associated with radial glia (RG)-like competence. Aligned microgrooves promote nuclear elongation, reduced Lamin A/C to B1 ratio, sustained {beta}-catenin activity, and distinct patterns of nuclear calcium dynamics, all of which merge before peak Pax6 expression. Pharmacological inhibition of mechanosensitive calcium signaling abolishes RG-associated marker induction while preserving nuclear remodeling, indicating that calcium-dependent pathways are required for Pax6 induction but are dispensable for the establishment of the underlying morphometric state. To quantitatively describe these transitions, we developed an interpretable model based on nuclear geometry and local cell density that identifies morphometric states associated with RG-like competence across experimental conditions. Application of this framework to embryonic mouse and human cortex revealed analogous signatures in native RG populations. Together, these findings indicate that tissue architecture influences RG-like competence through conserved nuclear morphometric states across developmental contexts.