In silico simulation reveals the importance of the initial basalward nucleokinesis for well-organized pseudostratification.

(A) Simulation of a single clone from S phase (0 min, white) to M phase (108 min, yellow), and further to the two daughter cells’ basal nucleokinesis (until 894 min, initially green during G1, turning white [entered S phase] and orange [exited from cell cycle = differentiated]) (see also S4A Fig and S23 Movie [left]). (B) Horizontal assembly of single IKNM-simulated clones results in the formation of highly pseudostratified virtual neuroepithelium (see also S23 Movie [right]). (C and D) Graphs comparing the trajectories of nuclei/somata between simulation (C, n = 60) and real observation (D, n = 60) (see also S4B–S4G Fig). (E–G) In silico removal (from t = 0 min) of the initial basalward propelling force (illustrated in S4A Fig, also visualized in S4G Fig, see Materials and methods for details) resulted in unsuccessful basal displacement of early G1 daughter cells’ nuclei/somata from the subapical space (E) and disruption of the virtual neuroepithelial structure (F and G; nuclear density in bin 10 is abnormally raised). Underlying data can be found in S1 Data. IKNM, interkinetic nuclear migration.