Practice question

Anchor cell versus ventral uterine precursor decision employs canonical lateral inhibition via Notch family receptors. Two equipotent cells Z1.ppp and Z4.aaa coexpress receptor LIN-12 Notch and ligand LAG-2 Delta-like. Initial stochastic difference amplifies via transcriptional feedback loop: cell with slightly higher LIN-12 signaling downregulates LAG-2 transcription via LAG-1 CSL repression, adopting ventral uterine fate, while neighbor with high LAG-2 low LIN-12 becomes anchor cell secreting LIN-3 and lag-2 for pi specification. LIN-12 intracellular domain released by presenilin SEL-12 cleavage translocates to nucleus ensuring single anchor cell.