ABOVE: © N.R. FULLER, SAYO-ART, LLC
During morphogenesis, cells cooperate to reliably build anatomical structures. Many living systems remodel and regenerate tissues or organs despite considerable damage—that is, they progressively reduce deviations from specific target morphologies, and halt growth and remodeling when those morphologies are achieved. Evolution exploits three modalities to achieve such anatomical homeostasis: biochemical gradients, bioelectric circuits, and biophysical forces. These interact to enable the same large-scale form to arise despite significant perturbations.
BIOCHEMICAL GRADIENTS
The best-known modality concerns diffusible intracellular and extracellular signaling molecules. Gene-regulatory circuits and gradients of biochemicals control cell proliferation, differentiation, and migration.
BIOELECTRIC CIRCUITS
The movement of ions across cell membranes, especially via voltage-gated ion channels and gap junctions, can establish bioelectric circuits that control large-scale resting potential patterns within and among groups of cells. These bioelectric patterns implement long-range coordination, feedback, and memory dynamics across cell fields. They underlie modular morphogenetic decision-making ...
