By Peter Weiss
Flicking a switch can now turn on much more than just the lights. Thanks to a technique developed by a team of biologists in California, a light pulse can activate or deactivate selected genes in cells.
Sae Shimizu-Sato of the University of California, Berkeley and the U.S. Department of
Agriculture in Albany, Calif., and her colleagues rendered a yeast gene light-triggerable by splicing plant genes into yeast cells. Those genes included one for a light-sensitive plant protein called a phytochrome, which changes shape upon absorbing certain wavelengths of red light.