Research offers new insight into light detection in vertebrates

October 16, 2015, University of Western Australia
Research offers new insight into light detection in vertebrates

Research carried out by scientists from The University of Western Australia, the University of Oxford and University College London will help better understand how light detection works in vertebrates.

The researchers tested zebrafish and found the fish to have more than 40 opsins (proteins that detect light), many more than previously known and the most found in any vertebrate.

The research found opsins in the eye and brain, but also in organs not thought to be directly affected by light, such as the heart, fins, gills, gonads, liver and gut.

Lead author Associate Professor Wayne Davies, Future Fellow from the School of Animal Biology at UWA, who worked with Professor Mark Hankins from the University of Oxford, said the researchers also found four new opsin families (named opn6-9) in zebrafish, amphibians, reptiles, birds and some mammals such as the platypus.

"Some of the photopigments discovered were found to be UV-sensitive and have the potential to assist with functions such as cell DNA repair," he said.

Professor Davies said the findings in the zebrafish could also be applied to other vertebrates that use similar systems to better understand light detection and its effect on the body.

"Light detection that aids vision in vertebrates is well understood, but the impact of light detection on other bodily functions has remained more of a mystery," he said.

"Specialised receptors in vertebrates' eye detect light to assist with colour vision and the formation of images.

"But non-visual systems use light detection in other ways, such as to synchronise biological rhythms for sleep and seasonal breeding."

Professor Davies said mammals use a single type of receptor in the eye which detects light and relays the information to a central "master" clock in the brain, which then regulates bodily functions.

"But in bony fish, cellular clocks are controlled by light directly, bypassing the cranial master control centre," he said.

"In humans, disruption of photosensory systems during activities such as shift-work and long-distance travel can lead to sleep dysfunction and jet-lag, but also to more serious physical and , and even death."

Professor Davies said the discoveries in would mean researchers could now begin to work out how light controls normal physiology, and assist with future research into diseases found in humans and other animals.

Explore further: New thesis maps the origin of colour vision

More information: Wayne I.L. Davies et al. An extended family of novel vertebrate photopigments is widely expressed and displays a diversity of function, Genome Research (2015). DOI: 10.1101/gr.189886.115

Related Stories

New thesis maps the origin of colour vision

March 26, 2015

Roughly 500 million years ago, the genome of vertebrate animals' early ancestors doubled in size, not just once but twice. This meant that suddenly there were several gene copies which were free to develop new functions. ...

Evolutionary novelties in vision

March 27, 2015

A new study from SciLifeLab at Uppsala University published in PLOS ONE shows that genes crucial for vision were multiplied in the early stages of vertebrate evolution and acquired distinct functions leading to the sophisticated ...

How the retina marches to the beat of its own drum

September 29, 2015

Researchers at Johns Hopkins and the University of Washington report new research that sheds light on how the retina sets its own biological rhythm using a novel light-sensitive pigment, called neuropsin, found in nerve cells ...

Recommended for you

How stem cells self-organize in the developing embryo

January 16, 2019

Embryonic development is a process of profound physical transformation, one that has challenged researchers for centuries. How do genes and molecules control forces and tissue stiffness to orchestrate the emergence of form ...

60 percent of coffee varieties face 'extinction risk'

January 16, 2019

Three in five species of wild coffee are at risk of extinction as a deadly mix of climate change, disease and deforestation puts the future of the world's favourite beverage in jeopardy, new research warned Wednesday.

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

1 / 5 (2) Oct 16, 2015

Excerpt: "Some of the photopigments discovered were found to be UV-sensitive and have the potential to assist with functions such as cell DNA repair," he said.

My comment: But first, tell us about the virucidal properties of UV light so that we can link the sun's biological energy to the de novo creation of nucleic acids and viruses to perturbed energy-dependent protein folding. Then, we can link nutrient energy-dependent ecological adaptations via what is currently know to serious scientists about RNA-mediated gene duplication and RNA-mediated DNA repair via nutrient-dependent amino acid substitutions and what was learned about microRNAs and adhesion proteins via the sequencing of the octopus genome.

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.