Synthetic Gene Networks That Count

Abstract

One, Two, Three Synthetic biologists take much of their inspiration from computing and electrical engineering, attempting to gain programmability in cells using analogous genetic circuits. Friedland et al. (p. 1199 ; see the Perspective by Smolke ) have constructed complementary Escherichia coli synthetic gene networks that keep track of prior molecular events to function as counters. These modular devices count up to three induction events over a range of frequencies and could be extended to higher numbers. Similar devices may find application in multi-event processes of cell biology, bioengineering, and, potentially, therapeutics.