Scientists digging deep in an iceberg off Greenland have discovered a fish with glowing green antifreeze running through its veins.
small assorted snail fish (Liberis GebusA new study found that ) contains the “highest expression levels” of anti-freeze proteins ever.
Similar to the way antifreeze helps regulate temperature From a vehicle’s engine in extreme conditions, some species have evolved to enjoy similar protection, particularly those that live in frigid environments such as the polar waters off green land.
“Antifreeze proteins stick to the surface of smaller ice crystals and slow or prevent them from growing into larger, more dangerous crystals,” said study co-author David Gruber, a research associate at the American Museum of Natural History (AMNH) and a Distinguished Professor of Biology at Baruch College. City University of New York, he told Live Science in an email. “Fishes from the north and south poles independently evolved these proteins.”
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Antifreeze proteins were first discovered in some Antarctic fish nearly 50 years ago, according to National Science Foundation (Opens in a new tab).
Unlike some types of cold-blooded reptiles and insects, fish cannot survive when their bodily fluids freeze, which can cause ice granules to form inside their cells and essentially turn them into fish suckers.
“The fact that these different antifreeze proteins have evolved independently in a number of different – and not closely related – lineages of fish shows[s] How critical they are to the survival of these organisms in these extreme habitats,” John Sparks, curator in AMNH’s Department of Ichthyology and co-author of the study, told Live Science in an email.
Snails produce antifreeze proteins “like any other protein and then excrete them into the bloodstream,” Gruber said. However, snails “appear to make antifreeze proteins in the top 1% of all other fish genes”.
Scientists found the tiny tadpole-like creature in 2019 during an expedition while exploring iceberg habitats off the coast of Greenland. During the trip – which was part of the expedition of Constantine S.
“The snail was one of the few species of fish that lived among the icebergs, in the crevices,” Gruber said. “It was amazing that such a small fish could survive in such an extremely cold environment without freezing.”
It is also rare for Arctic fish to exhibit bioluminescence, which is the ability to convert blue light into green, red, or yellow light, since there are long periods of darkness, especially in winter, at the poles. This characteristic is usually found in fish that swim in warm waters. This is the first reported case of an Arctic fish species showing this adaptation, according to AMNH post (Opens in a new tab).
The scientists also examined the biofluorescent properties of the snailfish and found “two different gene families encoding antifreeze proteins,” according to a separate statement, an adaptation that essentially helps them avoid turning into frozen fish sticks.
According to the statement, this impressive level of antifreeze production can help these species adapt to a subzero environment. It also raises the question of how snails are doing as ocean temperatures rise as a result Global Warming.
“Given the rapid warming of waters in the Arctic, these cold-water-adapted species will also have to compete with warm-water species that can now migrate northward and survive in higher latitudes (and which would not need to produce metabolically costly antifreeze proteins to survive). surviving in warmer Arctic waters),” Sparks said. “In the future, [antifreeze] Proteins may not provide an advantage anymore.”
The results were published on August 16 in the journal evolutionary bioinformatics (Opens in a new tab).
Originally published on Live Science.