Anchor cell

The anchor cell is a type of cell responsible for patterning during development in multicellular organisms. The anchor produces a signal which nearby equipotent precursor cells receive. A precursor cells may produce one or more secondary signals, which are received by other precursors. The combination of these signals–and variations in concentration–is used by these cells to determine their ultimate fate.

1. In Graded Signaling, a concentration gradient of some molecule–proportional to the distance from the anchor cell–acts to signal the precursor cell. Different concentrations produce different fates.
2. In Sequential Signaling, the anchor cell initiates a signaling cascade which begins in nearby precursors and spreads to those further away.
3. In Combined Signaling, the graded and sequential models are merged. Either concentration or a signaling cascade may specify precursor cell fate.^[1]