CAMBRIDGE, Mass. — The idea of taking apart a rat’s heart and transforming it into a tissue-engineered stingray first came to Kevin Kit Parker during a trip to the New England Aquarium with his daughter.

Four years later, a robotic ray that swims toward light has made the cover of Science Magazine and is pushing the limits of what’s possible in the design of machines powered by living cells.

A research team based at Harvard University’s Disease Biophysics Group, which Parker directs, created the translucent, penny-sized ray with a gold skeleton and silicone fins layered with the heart muscle cells of a rat.

It’s remote-controlled, guided by a blinking blue flashlight. Each burst of blue sets off a cascade of signals through the cells, which have been genetically-engineered to respond to light. The contraction of the tissue creates a downward motion on the ray’s body. When the tissue relaxes, the gold skeleton recoils — moving the fin upward again in an undulating cycle that mimics the graceful swimming of a real ray or skate.

Parker, whose research includes cardiac cell biology, launched the project as a method for learning more about the mysteries of the human heart and a step toward the far-off goal of building an artificial one. But the interdisciplinary project is also sparking interest in other fields, from marine biology to robotics.