A ligand/receptor trafficking clock governs self-renewal and abscission dynamics in pluripotent stem cells
Summary/AbstractHow extracellular cues are temporally integrated to regulate self-renewal and differentiation propensities across the cell cycle remains largely unresolved. We identify a ligand/receptor trafficking clock in rodent and human pluripotent stem cells (PSCs) in which the cyclic turnover of Netrin-1 and its receptors Neo1 and Unc5b (NNU) governs self-renewal capacity and abscission dynamics. In G1, NNU complexes undergo Clathrin-mediated internalization and lysosomal degradation, a process required for timely post-mitotic bridge abscission. At later stages of the cycle, NNU activate Src within early endosomes, inducing a genome-wide redistribution of the transcriptional co-activator Yap1. This reshapes gene regulatory networks by activating stemness- and ectoderm-associated transcriptional programs enriched for Sox2/Nanog binding and by repressing mesodermal- and cell cycle-related targets enriched for Sox2 and Tcf3. Functionally, recombinant Netrin-1 reduces functional heterogeneity and enhances clonogenicity in G1, uncovering a tractable strategy to canalize stem cell behavior. Collectively, our results reveal cell cycle-dependent ligand/receptor trafficking as a temporal clock that directly links membrane dynamics to epigenetic regulation and stem cell fate, opening new avenues for regenerative medicine.