Narrator: This is Science Today. For the first time, researchers at the University of California, San Francisco have a detailed look at how the most selective of all cellular gatekeepers works. Dr. Robert Stroud, a professor of biochemistry and biophysics at UCSF, says they've observed how a selective channel embedded in cell membranes decides what kind of molecules are allowed inside.
Stroud: This is a recent family of channels to have been discovered and yet, it is one of the most ancient in terms of origins. Its origins can be seen from bacteria that diverged from the human producing branches of evolution more than two thousand million years ago.
Narrator: Understanding the selective control of these channels, is key to understanding the nervous system.
Stroud: In this case, many of these families - the glycerol channel family, are regulated by other processes in the cells and so we are very interested in understanding that regulation and then possibly using that regulation in terms of thinking about human health.
Narrator: For Science Today, I'm Larissa Branin.