Practice question

Lateral inhibition generates fine-grained mosaic patterns via feedback where differentiating cell actively inhibits adjacent cells from adopting identical fate. Classic mechanism involves Notch-Delta: prospective neuron expresses Delta, activating Notch in neighbors, which upregulates Hes repressors that suppress neural differentiation genes like achaete-scute, forcing neighbors into epidermal fate. This amplifies small initial stochastic differences, producing spaced pattern of bristles, hair cells and neural precursors. It contrasts with lateral induction where signal promotes same fate. Mathematical modeling shows lateral inhibition creates alternating checkerboard patterns essential for sensory organ spacing, angiogenic tip-stalk selection and intestinal secretory patterning.