Cells step back in time

Many of us would like to be young again. Results from Maria Sequeira López, Ariel Gomez (University of Virginia, Charlottesville, VA), and colleagues show that a return to youthful activities is possible for at least some mature cell types.

These do-over cells are progeny of renin-secreting cells. The renin–angiotensin system controls body fluid and electrolyte levels. Although many cells make renin during development, those that hold this job in the adult are restricted to a small region of the kidney. During stresses such as dehydration, this population may be unable to make enough renin. To remedy the situation, more cells in and near the kidney begin to produce renin. Gomez's group shows that these helpers come from differentiated cells that had been embryogenic renin producers.

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