Endogenous bioelectrical currents are products of the concerted activity of ion channels, pumps, and transporters. They are also invaluable modulators of neural activity, though their role in guiding our physiology and disease progression is still a hotly debated topic within the scientific community. Dr. Elias Barriga, a group leader at the Cluster of Excellence, Physics of Life (PoL), highlights how the work of researchers from almost twenty years ago represented a major milestone, in a recent journal club piece for Nature Reviews Molecular Cell Biology.
Zhao and colleagues published their Nature study in 2006, using an in vitro electrotaxis assay to expose primary cultures of mouse cornea cells and other cell types to electric fields typical of mouse physiology. To establish if cell signalling pathways respond to these electric fields, Zhao et al. assessed the behaviour in both wild-type and mutant cells, and found that PI3Kγ and the tumour suppressor PTEN control the response to electrotaxis. They were also able to perturb ion flux by incubating cells with specific chemicals, and revealed that this treatment influenced corneal regeneration in vivo. As PI3Kγ and PTEN are involved in cellular responses to other stimuli such as chemotaxis, the authors propose that electrotaxis signals are integrated into the general directed cell migration program.
This seminal work inspired numerous future studies and Elias Barriga's own research on the role of endogenous currents in collective migration of cells. Several questions remain unanswered by the research community, including how endogenous electric fields form or whether there are specific electrosensors and, if so, how they integrate electric signals with molecular and mechanical sources of signalling to influence cell behaviour. It is therefore evident, that there is much work to do in elucidating the nature and importance of electrical signalling for human physiology and disease.
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Curious to learn more? Read the complete journal club piece, published in Nature Reviews Molecular Cell Biology.