Navigation Links
Antifreeze proteins in Antarctic fish prevent both freezing and melting
Date:9/23/2014

Antarctic fish that manufacture their own "antifreeze" proteins to survive in the icy Southern Ocean also suffer an unfortunate side effect, researchers funded by the National Science Foundation (NSF) report: The protein-bound ice crystals that accumulate inside their bodies resist melting even when temperatures warm.

"We discovered what appears to be an undesirable consequence of the evolution of antifreeze proteins in Antarctic notothenioid fish," said University of Oregon doctoral student Paul Cziko, who led the research with University of Illinois animal biology professors Chi-Hing "Christina" Cheng and Arthur DeVries. "What we found is that the antifreeze proteins also stop internal ice crystals from melting. That is, they are anti-melt proteins as well."

The new finding was reported in the Proceedings of the National Academy of Sciences.

Five families of notothenioid fish inhabit the Southern Ocean, the frigid sea that encircles Antarctica. Their ability to live in the icy seawater is so extraordinary that they make up more than 90 percent of the fish biomass of the region.

With NSF support, Arthur DeVries discovered antifreeze proteins in Antarctic notothenioid fish in the late 1960s, and was the first to describe how the proteins bind to ice crystals in the blood to prevent the fish from freezing.

The most recent antifreeze discovery was supported by a grant from NSF's Division of Polar Programs.

The Division manages the United States Antarctic Program, through which it coordinates all U.S. research on the southernmost continent and provides the logistical framework to support the science.

This long-standing and continuously refined work on the antifreeze properties of Antarctic fish exemplifies one of the best and defining features of good science," said Charles Amsler, organisms and ecosystems program director in Polar Programs.

"These researchers not only have for decades consistently produced new and exciting finds that contribute to our understanding of Antarctic ecosystems, but very often those new finds have led to new questions and deeper understandings across biology as a whole," he added.

In the new study, the team investigated whether the antifreeze protein-bound ice crystals inside these fish would melt as expected when temperatures warmed.

When researchers warmed the fish to temperatures above the expected melting point, some internal ice crystals failed to melt. Ice that doesn't melt at its normal melting point is referred to as "superheated."

The researchers also found ice crystals in wild notothenioid fish swimming in relatively warmer Antarctic summer waters, at temperatures where they would be expected to be free of ice. By testing the antifreeze proteins in the lab, the team found that these proteins also were responsible for preventing the internal ice crystals from melting.

"Our discovery may be the first example of ice superheating in nature," Cheng said.

A diver himself, Cziko worked with other divers to place and maintain a temperature-logging device in Antarctica's McMurdo Sound, one of the coldest marine environments on the planet. The device recorded ocean temperatures there for 11 years, a substantial portion of notothenioids' lifespan. Not once in that time did temperatures increase enough to overcome the antifreeze proteins' anti-melting effect to completely rid the fish of their internal ice, the researchers report.

The researchers suspect that the accumulation of ice inside the fish could have adverse physiological consequences, but none have yet been discovered.

If the fish are destined to carry ice crystals around all their lives, Cheng said, it is conceivable that ice particles could obstruct small capillaries or trigger undesired inflammatory responses. Cziko likens the potential threat to dangers posed by asbestos in the lungs or blood clots in the brain.

"Since much of the ice accumulates in the fish spleens, we think there may be a mechanism to clear the ice from the circulation," he said.

"This is just one more piece in the puzzle of how notothenioids came to dominate the ocean around Antarctica," he said. "It also tells us something about evolution. That is, adaptation is a story of trade-offs and compromise. Every good evolutionary innovation probably comes with some bad, unintended effects."

The long-term temperature record of McMurdo Sound produced in the study also "will prove to be of great importance and utility to the polar research community that is addressing organismal responses to climate change in this coldest of all marine environments," Cheng said.


'/>"/>

Contact: Peter West
pwest@nsf.gov
703-292-7530
National Science Foundation
@NSF
Source:Eurekalert  

Related biology news :

1. Dance of water molecules turns fire-colored beetles into antifreeze artists
2. Not just cars, but living organisms need antifreeze to survive
3. Study: Antifreeze proteins in Antarctic fishes prevent freezingand melting
4. More effective method of imaging proteins
5. Gold nanoantennas detect proteins
6. Discovery of a new family of key mitochondrial proteins for the function and viability of the brain
7. Discovery of plant proteins may boost agricultural yields and biofuel production
8. UCLA researchers develop way to strengthen proteins with polymers
9. Discovered a new checkpoint of cell cycle control through joint action of 2 proteins
10. A non-invasive intracellular thermometer with fluorescent proteins has been created
11. Speeding up drug discovery with rapid 3-D mapping of proteins
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Antifreeze proteins in Antarctic fish prevent both freezing and melting
(Date:6/13/2020)... ... June 11, 2020 , ... Bode Technology ... of its forensic genealogy team. Bode’s Forensic Genealogy Service (FGS) continues ... and DNA analysis methods. The team has added experienced genealogists, each having over ...
(Date:6/5/2020)... ... June 04, 2020 , ... “Although we are disappointed to have to ... attendees, staff, and the public. We remain committed to creating a global platform ... virtually,” said Julie Sutcliffe, President of WMIS. , The abstract deadline ...
(Date:5/28/2020)... ... ... CrucialTrak, a global designer and manufacturer of biometric access control systems, today announced ... sell its complete line of biometric readers and access gates . CEG is ... , Brett Mason, CrucialTrak’s Director of Channel Sales for the Americas is very ...
Breaking Biology News(10 mins):
(Date:7/7/2020)... , ... July 06, 2020 , ... ... Awards. Entries from Roche, Eli Lilly, Bristol-Myers Squibb, the University of Chicago, Massachusetts ... Bio-IT World has hosted an elite awards program, highlighting outstanding examples of how ...
(Date:6/28/2020)... ... June 25, 2020 , ... With the COVID-19 ... or drug treatment. In an effort to better understand the cellular responses to ... largest imaging dataset portraying therapeutic compound effects from over 1,600 approved and referenced ...
(Date:6/23/2020)... Ariz. (PRWEB) , ... June 22, 2020 , ... ... is now offering an Amniosomes special offer. This includes buy three, get the ... should call (888) 568-6909. , Amniotic derived exosomes, known as exosomes, have been ...
(Date:6/11/2020)... ... June 09, 2020 , ... PathSensors Inc., a Baltimore biotechnology ... Research (SBIR) program funded by the National Institute of Food and Agriculture (NIFA) ... The project’s goal was to engineer and develop a field-deployable instrument for portable ...
Breaking Biology Technology: