Notch signaling is a highly conserved, cell-contact-based mechanism critical for developmental patterning and tissue homeostasis. While mathematical models have captured many dynamical features of Notch signaling, the mechanisms enabling its propagation across non-adjacent cells remain less understood. A key hypothesis suggests that active cellular processes, such as transport along filopodia, extend Notch signals beyond direct cell-cell contact. In this study, we develop a comprehensive mean-field model to investigate the spatial distributions of molecular motors and their cargo, NICD (the active intracellular domain of Notch), within filopodia. By incorporating diffusion, active transport, binding/unbinding kinetics, and traffic jamming effects, our model provides insights into the mechanisms governing the transport of activated Notch signals from the filopodial tip to the cell body, where it regulates gene expression and cellular responses.
Yahayah et al. (Sun,) studied this question.