A. Getting Blind Nerve Cells to See the Light
Narrator: This is Science Today. ‘Blind' nerve cells were able to see the light in a recent study at the University of California, Berkeley. Richard Kramer, a professor of molecular and cell biology says although it's a long way off, their technique may one day lead to therapy to restore sight to those who have lost it due to disease. Kramer's group inserted a light-activated switch into brain cells normally insensitive to light.
Kramer: It's a combination of a synthetic chemical made by our chemistry colleagues at UC Berkeley and a genetically engineered protein that is responsible for the electrical signaling in nerve cells. And the idea is you put these two things together and now you can make those signaling proteins directly sensitive to light. And so if you shine light on cells that have these proteins, those cells now should become responsive to light. We're most interested in doing this in the visual system, in the eye, where of course light is readily accessible to your nervous system, particularly the retina, which is in the back of the eye.
Narrator: For Science Today, I'm Larissa Branin.
B.
Tracking How Psychological Stress Leads to Cellular Damage
Narrator: This is Science Today. A University of California, San Francisco study suggested an actual cellular mechanism for how chronic stress may cause premature aging of cells and the onset of disease. Lead author Elissa Epel admits they are now flooded with follow-up questions.
Epel: We know now that there is a link between stress and these markers of cell aging, we don't know how. We don't know what's in the black box between mind and cell aging and we are trying to map out how the biochemical pathway that will help us explain how perceptions of stress can lead to this type of cellular damage.
Narrator: Epel says they will primarily be examining people.
Epel: Because we can only understand resilience of stress by really understanding how people cope with chronic stress. So we're now examining dementia caregivers and we're following them for two years and so we're looking at factors such as genetics, personality and primarily how they cope with caregiving stress and looking at how that predicts different aspects of health years later.
Narrator: For Science Today, I'm Larissa Branin.
C.
Charting the Evolutionary History of Hawaiian Spiders
Narrator: This is Science Today. By studying the DNA of 16 species of Hawaiian spiders, biologist Rosemary Gillespie of the University of California, Berkeley has discovered much about evolution. The spiders were found throughout the Hawaiian Islands, but they could be traced back to a common ancestor from Kauai , Hawaii's oldest island at 5 million years old.
Gillespie: You can actually see exactly how species have changed as they've gone from one island to the next. So, it shows us how evolution works and how it's tightly tied to the environment.
Narrator: But with the big island becoming more populated and new species of animals emerging, Gillespie wonders if the once isolated ecosystem of Hawaii will maintain its balance.
Gillespie: The next step will be to see how they're going to be impacted by the onslaught of species coming in now. Whether we can maintain some semblance of these ancient processes that have been going on for millions of years or whether we can't. I would say we can and we need to learn how too.
Narrator: For Science Today, I'm Larissa Branin.
D.
Atherosclerosis the Target for New Drug Therapies
Narrator: This is Science Today. Atherosclerosis, a disease in which plaque builds up in the inner lining of an artery, is a major target for the development of new drugs. Christopher Glass, a professor of cellular and molecular medicine at the University of California, San Diego, says the cell called a macrophage, which normally plays a role in immunity, also plays a key role in the development of atherosclerosis.
Glass: The macrophage is a cell that crawls into the artery wall and picks up cholesterol that is the cholesterol that accumulates within the artery wall and ultimately, is associated with the development of what we call atherosclerotic lesions. These are blockages in the artery. And so what we would like to be able to do is identify new ways of preventing the accumulation of macrophages in the blood vessel wall and their accumulation of cholesterol.
Narrator: Glass' group discovered that anti-diabetic drugs also activate proteins that can alter the ability of macrophages to pick up cholesterol.
Glass: The ability of these drugs to inhibit atherosclerosis suggested the whole new therapy to target that was different from lowering glucose levels in diabetics.
Narrator: For Science Today, I'm Larissa Branin.
E.
A Small Ocean Glider with Far-Reaching Goals
Narrator: This is Science Today. Oceanographer Russ Davis of the Scripps Institution of Oceanography at the University of California, San Diego seemed to turn an early childhood hobby into a scientific career.
Davis: I grew up making model airplanes and now I'm making model airplanes that go under the water.
Narrator: This so-called underwater model airplane that Davis refers to is actually an autonomous underwater vehicle, or AUV, which is called Spray. Davis helped design Spray, which recently made history crossing the Gulf Stream from Massachusetts to Bermuda. Davis says Spray's voyage may some day even benefit national interests.
Davis: I was at a meeting where the Navy is looking into how to use these technologies for measuring what the sound speed profiles are in the ocean to tell what sound propagation is like. To maybe even listening for targets.
Narrator: The current goal is to see if Spray can make a round-trip voyage from Massachusetts to Bermuda. For Science Today, I'm Larissa Branin.
