Research could lead to new treatments for blindness

January 26, 2005

Scientists have discovered how to make cells sensitive to light in what may lead to a new approach to treating certain forms of blindness.

The research, published today (January 27) in the science journal Nature, shows that a gene called melanopsin causes nerve cells to become photoreceptive.

The team of experts from The University of Manchester and Imperial College London found that activating melanopsin in cells that don't normally use the gene makes them sensitive to light.

"The melanopsin made the cells photoreceptive which tells us that this protein is able to absorb light," said Dr Rob Lucas, who led the team in Manchester.

"This discovery might provide food for thought for scientists looking for ways of treating visual loss."

Dr Lucas, whose research concerns the effect light has on our daily rhythms, said the classical view of how the eye sees is through photoreceptive cells in the retina called rods and cones.

But Dr Lucas and Professor Hankins were part of a team that recently discovered a third type of photoreceptor, although the mechanisms of how it worked had not been fully understood - until now.

"Over the last few years it has become increasingly accepted that we have a third system that uses melanopsin and has lain undetected during years of vigorous scientific investigation," said Dr Lucas.

"For this latest research, we introduced melanopsin to cells that do not normally use it. What we found is that the cell becomes photosensitised and is able to produce a biological signal.

"The discovery that melanopsin is capable of making cells photosensitive has given us a unique opportunity to study the characteristics of this interesting protein."

For some years scientists have been exploring ways of restoring light detection to those blind people who have lost their rods and cones.

One implication of this research is that using melanopsin to make nerve cells in the eye photoreceptive may represent an entirely new approach to this problem.

Co-author and leader of the London team, Professor Mark Hankins of Imperial College, said: "It is quite remarkable that the activation of a single gene can create a functional photoreceptor."

"It is an important proof of principle that melanopsin can make non-light sensitive cells receptive to light and, although not a cure, could have applications in treating some forms of blindness."

Researchers also believe that defects in melanopsin action could be responsible for other human conditions, including some sorts of depression and insomnia.

"The truth is, we just don't know what else melanopsin could be responsible for," said Dr Lucas. "But now that we understand the role of this gene we can further investigate its influence in such areas as mood and sleep patterns."

The research team is collaborating with engineers at Imperial to develop a functional retinal prosthesis that would allow information from the light-responsive cells to be used by the brain to form images.
Notes to editors:
1. Hi-resolution images of Dr Lucas and the Manchester team available on request. Please refer to the low-resolution contact sheet attached.
2. The paper, 'Addition of human melanopsin renders mammalian cells photoreceptive', will be published in the science journal Nature on Thursday, January 27, 2005.
3. The research was supported by a Wellcome Trust Showcase Award and the BBSRC.
4. The University of Manchester, created from the merger of The Victoria University of Manchester and UMIST in October 2004, is the UK's largest university with 9,000 staff and 28,802 full-time-equivalent students and an income £490.5m.

University of Manchester

Related Nerve Cells Articles from Brightsurf:

Nerve cells let others "listen in"
How many ''listeners'' a nerve cell has in the brain is strictly regulated.

Nerve cells with energy saving program
Thanks to a metabolic adjustment, the cells can remain functional despite damage to the mitochondria.

Why developing nerve cells can take a wrong turn
Loss of ubiquitin-conjugating enzyme leads to impediment in growth of nerve cells / Link found between cellular machineries of protein degradation and regulation of the epigenetic landscape in human embryonic stem cells

Unique fingerprint: What makes nerve cells unmistakable?
Protein variations that result from the process of alternative splicing control the identity and function of nerve cells in the brain.

Ragweed compounds could protect nerve cells from Alzheimer's
As spring arrives in the northern hemisphere, many people are cursing ragweed, a primary culprit in seasonal allergies.

Fooling nerve cells into acting normal
In a new study, scientists at the University of Missouri have discovered that a neuron's own electrical signal, or voltage, can indicate whether the neuron is functioning normally.

How nerve cells control misfolded proteins
Researchers have identified a protein complex that marks misfolded proteins, stops them from interacting with other proteins in the cell and directs them towards disposal.

The development of brain stem cells into new nerve cells and why this can lead to cancer
Stem cells are true Jacks-of-all-trades of our bodies, as they can turn into the many different cell types of all organs.

Research confirms nerve cells made from skin cells are a valid lab model for studying disease
Researchers from the Salk Institute, along with collaborators at Stanford University and Baylor College of Medicine, have shown that cells from mice that have been induced to grow into nerve cells using a previously published method have molecular signatures matching neurons that developed naturally in the brain.

Bees can count with just four nerve cells in their brains
Bees can solve seemingly clever counting tasks with very small numbers of nerve cells in their brains, according to researchers at Queen Mary University of London.

Read More: Nerve Cells News and Nerve Cells Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to