Researchers find new light-sensing mechanism in neurons

March 3, 2011, University of California - Irvine
This image shows blue-light sensing arousal neurons. Credit: UCI

A UC Irvine research team led by Todd C. Holmes has discovered a second form of phototransduction light sensing in cells that is derived from vitamin B2. This discovery may reveal new information about cellular processes controlled by light.

For more than 100 years, it had been believed that the phototransduction process was solely based on a chemical derived from vitamin A called retinal. Phototransduction is the conversion of light signals into in photoreceptive and underlies both image-forming and non-image-forming light sensing.

In discovering this new light-sensing phototransduction mechanism, the UCI scientists found that phototransduction can also be mediated by a called cryptochrome, which uses a B2 vitamin chemical derivative for light sensing. Cryptochromes are blue-light photoreceptors found in circadian and arousal neurons that regulate slow biochemical processes, but this is the first time they have been linked to rapid phototransduction.

Their work appears March 3 on online Express site for the journal Science.

"This is totally novel mechanism that does not depend on retinal," said Holmes, a professor of physiology & biophysics. "This discovery opens whole new technology opportunities for adapting light-sensing proteins to drive medically relevant cellular activities."

This basic science breakthrough – "which literally and figuratively came 'out of the blue,'" Holmes said – has implications in the fast-growing field of optogenetics. Optogenetics combines optical and genetic research techniques to probe neural circuits at the high speeds needed to understand brain information processing. In one area, it is being used to understand how treatments such as deep brain massage can aid people with neurodegenerative diseases.

Holmes' team found that cryptochrome mediates phototransduction directly in fruit fly circadian and arousal neurons in response to blue-light wavelengths. The researchers also found that they could genetically express cryptochrome in neurons that are not ordinarily electrically responsive to light to make them responsive.

Related Stories

Recommended for you

Fabric imbued with optical fibers helps fight skin diseases

February 23, 2018
A team of researchers with Texinov Medical Textiles in France has announced that their PHOS-ISTOS system, called the Fluxmedicare, is on track to be made commercially available later this year. The system consists of a piece ...

DNA gets away: Scientists catch the rogue molecule that can trigger autoimmunity

February 22, 2018
A research team has discovered the process - and filmed the actual moment - that can change the body's response to a dying cell. Importantly, what they call the 'Great Escape' moment may one day prove to be the crucial trigger ...

Low-calorie diet enhances intestinal regeneration after injury

February 22, 2018
Dramatic calorie restriction, diets reduced by 40 percent of a normal calorie total, have long been known to extend health span, the duration of disease-free aging, in animal studies, and even to extend life span in most ...

Artificial intelligence quickly and accurately diagnoses eye diseases and pneumonia

February 22, 2018
Using artificial intelligence and machine learning techniques, researchers at Shiley Eye Institute at UC San Diego Health and University of California San Diego School of Medicine, with colleagues in China, Germany and Texas, ...

Gut microbes protect against sepsis—mouse study

February 22, 2018
Sepsis occurs when the body's response to the spread of bacteria or toxins to the bloodstream damages tissues and organs. The fight against sepsis could get a helping hand from a surprising source: gut bacteria. Researchers ...

Fertility breakthrough: New research could extend egg health with age

February 22, 2018
Women have been told for years that if they don't have children before their mid-30s, they may not be able to. But a new study from Princeton University's Coleen Murphy has identified a drug that extends egg viability in ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.