WikimediaPetar MiloševicVisual pigments in animal eyes absorb a variety of different wavelengths of light, yet each contains precisely the same chromophore—the light-absorbing part of the molecule. Now, thanks to an elaborate protein-engineering project, scientists in Michigan have revealed how this same chromophore, called retinal, is capable of detecting different colors in different cells of the retina. As a by-product of the study, published today (December 6) in Science, the researchers have also generated a suite of designer pigments, which have a potential spectrum of applications.
“We started this project from a very esoteric standpoint—what is going on in color vision?” said Babak Borhan, professor of synthetic and bio-organic chemistry at Michigan State University, who led the study. “But we’ve completely moved to a different realm now, that of potential applications.” For example, Borhan’s palette of pigments could be used to tag proteins of interest, color specific cell types, and more.
The ability of a chromophore to change the wavelengths it absorbs—a phenomenon known as spectral tuning—has fascinated biologists for decades, said Tom Sakmar, professor of molecular biology and biochemistry at The Rockefeller University in New York. All animals use retinal for color vision, he explained, but retinal’s absorption properties can range from blue wavelengths right through to reds depending on ...
