Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Does missing gene point to nocturnal existence for early mammals?

12.10.2006
A gene that makes cells in the eye receptive to light is missing in humans, researchers have discovered.

They say that whereas some animals like birds, fish and amphibians have two versions of this photoreceptor, mammals, including humans, only have one.

The findings – published in the Public Library of Science journal PLoS Biology – reveal how our experience of the light environment may be impoverished compared to other vertebrates and fits with the suggestion that early mammals were at one time wholly nocturnal creatures.

“The classical view of how the eye sees is through photoreceptive cells in the retina called rods and cones,” explained Dr Jim Bellingham, who led the research at The University of Manchester.

“But, recently, a third photoreceptor was discovered that is activated by a gene called melanopsin. This melanopsin photoreceptor is not linked to sight but uses light for non-visual processes, such as regulating our day-night rhythms and pupil constriction.”

Although the melanopsin gene is present in all vertebrates, the version in mammals was unusually different to that found in fish, amphibians and birds.

“At first, we put this genetic anomaly between mammals and other vertebrates down to evolutionary differences,” said Dr Bellingham, who is based in the Faculty of Life Sciences.

“But we have now learnt that other vertebrates have a second melanopsin gene – one that matches the one found earlier in mammals and humans. The first melanopsin gene found in the other classes of vertebrates does not exist in mammals.”

It is not yet clear how the functions of the two melanopsins differ but having different cone genes or ‘opsins’ allows vertebrates to detect different wavelengths of light and allows them to see colour.

The Manchester team now hope to find out whether the two melanopsin genes in non-mammals play similar or different roles in non-visual light detection and so provide clues as to the implications of only having one melanopsin gene.

“The two genes and their associated proteins have been maintained in vertebrates for hundreds of millions of years, only for one of them to be lost in mammals.

“We are keen to discover why this might have happened – perhaps the early mammals were at one stage nocturnal and had no need for the second gene, for instance. We also want to find out what losing one of these genes means for humans.”

Aeron Haworth | alfa
Further information:
http://www.manchester.ac.uk

Further reports about: Melanopsin melanopsin gene nocturnal vertebrates

More articles from Life Sciences:

nachricht Antimicrobial substances identified in Komodo dragon blood
23.02.2017 | American Chemical Society

nachricht New Mechanisms of Gene Inactivation may prevent Aging and Cancer
23.02.2017 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

From rocks in Colorado, evidence of a 'chaotic solar system'

23.02.2017 | Physics and Astronomy

'Quartz' crystals at the Earth's core power its magnetic field

23.02.2017 | Earth Sciences

Antimicrobial substances identified in Komodo dragon blood

23.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>