Role of pH regulation in electrotaxis

Naturally occurring steady-state electrical signals are found within the extracellular and intracellular space of organisms. These electrical signals arise from polarized

ion transport via the distinct localization and differential functioning of ion channels and pumps. Resulting ionic gradients cause spatial voltage differences, thus creating electric fields. Directional cell migration as a response to electric fields is termed electrotaxis. In our setup, human skin-derived immortalized keratinocytes respond to exogenously applied electric fields of physiological strength by electrotaxing to the cathode.  We speculate that electrotaxis may be controlled by an ancient polarity pathway involving proton translocation, previously identified in lower organisms such as plants and yeast. The electrotaxis response mediated by asymmetrically localized or activated proton transporters may communicate  with established polarity pathways such as the non-canonical Wnt pathway to promote cell migration.