Often referred to as the "body clock," circadian rhythm controls what time of day people are most alert, hungry, tired, or physically primed due to a complex biological process that is not unique to humans. Circadian rhythms, which oscillate over a roughly 24-hour cycle in adaptation to the Earth's rotation, have been observed in most of the planet's plants, animals, fungi, and cyanobacteria, and are responsible for regulating many aspects of organisms' physiological, behavioral and metabolic functions. Now, scientists, led by the pioneering Harvard synthetic biologist Pamela Silver, Ph.D., have harnessed the circadian mechanism found in cyanobacteria to transplant the circadian wiring into a common species of bacteria that is naturally non-circadian. The novel work, which for the first time demonstrates the transplant of a circadian rhythm, is described in an open-access article published online on June 12, 2015 in Science Advances. "By looking at systems in nature as modular, we think like engineers to manipulate and use biological circuits in a predictable, programmable way," said Dr. Silver, who is a Core Faculty member at the Wyss Institute for Biologically Inspired Engineering at Harvard University and a Professor in the Department of Systems Biology at Harvard Medical School. Dr. Silver's team used this methodology to successfully transplant a circadian rhythm into the bacterial species E. coli, which is widely used as a "workhorse" cell species by biologists due to how well it is understood and the ease with which E. coli can be genetically altered. The genetically engineered circadian E.Login Or Register To Read Full Story