Featured Research

from universities, journals, and other organizations

Not Just Through The Eyes: Squid 'Sight' Offers Insight Into Treating Human Eye Diseases

Date:
June 3, 2009
Source:
University of Wisconsin-Madison
Summary:
It's hard to miss the huge eye of a squid. But now it appears that certain squids can detect light through an organ other than their eyes as well.

New research shows that the light-emitting organ some squids use to camouflage themselves to avoid being seen by predators also detects light.
Credit: Image courtesy of University of Wisconsin-Madison

It's hard to miss the huge eye of a squid. But now it appears that certain squids can detect light through an organ other than their eyes as well.

That's what researchers at the University of Wisconsin-Madison report in the June 2 issue of the Proceedings of the National Academy of Sciences.

The study shows that the light-emitting organ some squids use to camouflage themselves to avoid being seen by predators — usually fish sitting on the ocean floor — also detects light.

The findings may lead to future studies that provide insight into the mechanisms of controlling and perceiving light.

"Evolution has a 'toolkit' and when it needs to do a particular job, such as see light, it uses the same toolkit again and again," explains lead author Margaret McFall-Ngai, a professor of medical microbiology and immunology at the UW-Madison School of Medicine and Public Health (SMPH). "In this case, the light organ, which comes from different tissues than the eye during development, uses the same proteins as the eye to see light."

In studying the squid for the past 20 years, McFall-Ngai and her colleagues have been drawn to the fact that the squid-light organ is a natural model of symbiosis — an interdependent relationship between two different species in which each benefits from the other.

In this case, the light organ is filled with luminous bacteria that emit light and provide the squid protection against predators. In turn, the squid provides housing and nourishment for the bacteria.

The UW-Madison researchers have been intrigued by the light organ's "counterillumination" ability — this capacity to give off light to make squids as bright as the ocean surface above them, so that predators below can't see them.

"Until now, scientists thought that illuminating tissues in the light organ functioned exclusively for the control of the intensity and direction of light output from the organ, with no role in light perception," says McFall-Ngai. "Now we show that the E. scolopes squid has additional light-detecting tissue that is an integral component of the light organ."

The researchers demonstrated that the squid light organ has the molecular machinery to respond to light cues. Molecular analysis showed that genes that produce key visual proteins are expressed in light-organ tissues, including genes similar to those that occur in the retina. They also showed that, as in the retina, these visual proteins respond to light, producing a physiological response.

"We found that the light organ in the squid is capable of sensing light as well as emitting and controlling the intensity of luminescence," says co-author Nansi Jo Colley, SMPH professor of ophthalmology and visual sciences and of genetics.

Adds McFall-Ngai, "The tissues may perceive environmental light, providing the animal with a mechanism to compare this light with its own light emission."

McFall-Ngai's large research program into the relatively simple squid-light organ symbiosis aims to shed light on symbiosis affecting humans.

"We know that humans house trillions of bacteria associated with components of eight of their 10 organ systems," she says. "These communities of bacteria are stable partners that make us healthy."

Both Colley and McFall-Ngai are members of the UW-Madison Eye Research Institute.


Story Source:

The above story is based on materials provided by University of Wisconsin-Madison. Note: Materials may be edited for content and length.


Cite This Page:

University of Wisconsin-Madison. "Not Just Through The Eyes: Squid 'Sight' Offers Insight Into Treating Human Eye Diseases." ScienceDaily. ScienceDaily, 3 June 2009. <www.sciencedaily.com/releases/2009/06/090601182828.htm>.
University of Wisconsin-Madison. (2009, June 3). Not Just Through The Eyes: Squid 'Sight' Offers Insight Into Treating Human Eye Diseases. ScienceDaily. Retrieved August 27, 2014 from www.sciencedaily.com/releases/2009/06/090601182828.htm
University of Wisconsin-Madison. "Not Just Through The Eyes: Squid 'Sight' Offers Insight Into Treating Human Eye Diseases." ScienceDaily. www.sciencedaily.com/releases/2009/06/090601182828.htm (accessed August 27, 2014).

Share This




More Plants & Animals News

Wednesday, August 27, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Super Healthful Fruits and Vegetables: Which Are Best?

Super Healthful Fruits and Vegetables: Which Are Best?

Ivanhoe (Aug. 27, 2014) We all know that it is important to eat our fruits and vegetables but do you know which ones are the best for you? Video provided by Ivanhoe
Powered by NewsLook.com
Raw: Firefighters Rescue Puppy Stuck in Tire

Raw: Firefighters Rescue Puppy Stuck in Tire

AP (Aug. 26, 2014) It took Houston firefighters more than an hour to free a puppy who got its head stuck in a tire. (Aug. 26) Video provided by AP
Powered by NewsLook.com
Have You Ever Been 'Sleep Drunk?' 1 in 7 Has

Have You Ever Been 'Sleep Drunk?' 1 in 7 Has

Newsy (Aug. 26, 2014) A study published in the journal "Neurology" interviewed more than 19,000 people and found 15 percent suffer from being "sleep drunk." Video provided by Newsy
Powered by NewsLook.com
Activists Urge NYC Mayor to Ban Carriage Horses

Activists Urge NYC Mayor to Ban Carriage Horses

AP (Aug. 26, 2014) A group of New Yorkers are putting Mayor Bill de Blasio on notice for what they say is reneging on his campaign promise to ban carriage horses. They rallied Tuesday near the mayor's Gracie Mansion home. (Aug. 26) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins