Electrical signalling in biology is typically associated with action potentials—transient spikes in membrane voltage that return to baseline. Hodgkin–Huxley and related conductance-based models of electrophysiology belong to a more general class of reaction–diffusion equations that could, in principle, support the spontaneous emergence of patterns of membrane voltage that are stable in time but structured in space. Here, we show theoretically and experimentally that homogeneous or nearly homogeneous tissues can undergo spontaneous spatial symmetry breaking through a purely electrophysiological mechanism, leading to the formation of domains with different resting potentials separated by stable bioelectrical domain walls. Transitions from one resting potential to another can occur through long-range migration of these domain walls. We map bioelectrical domain wall motion using all-optical electrophysiology in an engineered cell line and in human induced pluripotent stem cell (iPSC)-derived myoblasts. Bioelectrical domain wall migration may occur during embryonic development and during physiological signalling processes in polarized tissues. These results demonstrate that nominally homogeneous tissues can undergo spontaneous bioelectrical spatial symmetry breaking.

生物学中的电信号通常与动作电位相关——膜电压的瞬态尖峰返回基线。Hodgkin-Huxley 和相关的基于电导的电生理学模型属于更一般的一类反应-扩散方程，原则上可以支持时间稳定但空间结构化的膜电压模式的自发出现。在这里，我们从理论上和实验上表明，均质或近乎均质的组织可以经历自发的空间对称性，突破纯电生理机制，导致形成由稳定的生物电畴壁分隔的具有不同静息电位的域。通过这些畴壁的远程迁移，可以发生从一种静息电势到另一种静息电势的转变。我们使用全光电生理学在工程细胞系和人类诱导多能干细胞 (iPSC) 衍生的成肌细胞中绘制生物电畴壁运动。生物电畴壁迁移可能发生在胚胎发育过程中和极化组织中的生理信号过程中。这些结果表明，名义上均质的组织可以经历自发的生物电空间对称性破坏。