Introduction Arctic fish display a remarkable case of adaptation, living in in low temperatures around 0˚C with areas of ice that can be -1.9˚C (DeVries, 1971). The ability for Arctic fish to thrive in such a low temperature environment is made possible by a class of proteins called Antifreeze proteins. Antifreeze proteins (AFPs) and Antifreeze glycoproteins (AFGPs) are polypeptides that are biosynthesized in animals, plants and fungi that prevent ice crystal formation (Griffith & Ewart, 1995). The most widely accepted mechanism for the prevention of ice formation by AFPs and AFGPs is called the adsorption-inhibition mechanism, which describes that the protein binds to water molecules and separates water molecules at a certain distance. This separation distance is large enough to inhibit ice crystal formation and prevent recrystallization (Raymond et al., 1977). The complexity of AFPs and AFGPs provoke several important questions regarding their origins, such as: From where did AFPs and AFGPs originate? How conserved are AFPs and AFGPs among different species of polar fish, are they conserved? Through what mechanisms have antifreeze proteins, and antifreeze glycoproteins evolved? What environmental or ecological stresses influenced the proliferation of AFPs and AFGPs in cold-water fish? The stunning amount of diversity found in antifreeze proteins is evident of a fascinating evolutionary story. Exploring the phylogenetic and molecular data from different species of cold-water fish is a common starting point for determining the origins of antifreeze proteins. Antifreeze proteins can be divided into two groups, the AFPs and AFGPs. Of the AFPs, there are currently four known types: I, II, III and IV (Cheng et al., 1998). By examining... ... middle of paper ... ... similarities between proteins exhibiting homology, and inspecting the AFP nucleic acid sequence in comparison with proteins showing similarities. The driving force for most of these evolutionary events is supported by colder climates. Oceanic cooling most certainly added selective pressures towards polar fish, bearing in mind the evidence that suggests protein homology, it is possible to propose that the aforementioned AFPs are derived from different proteins seen today. Environment stress influencing AFP and AFGP proliferation is most supported by glaciation and cooling periods. Evidence from Pleistocene cooling events covers several AFPs and the AFGPs as a relevant selective pressure. As the ever-expanding amount of protein sequences become more available, I also expect the accuracy for pinpointing protein homology to elucidate explicit evolutionary mechanisms.
Levis, N. A., Yi, S. X., & Lee, R. E. (2012). Mild desiccation rapidly increases freeze tolerance of the goldenrod gall fly, eurosta solidaginis: evidence for drought-induced rapid cold-hardening. Manuscript submitted for publication, Available from Journal of Experimental Biology. (215, 3768-3773)Retrieved from http://jeb.biologists.org/content/215/21/3768.full
"The Species of the Secondary Protein Structure. Virtual Chembook - Elmhurst College. Retrieved July 25, 2008, from http://www.cd http://www.elmhurst.edu/chm/vchembook/566secprotein.html Silk Road Foundation. n.d. - n.d. - n.d.
...ightly to allow some air to pass underneath it. Snakes can regulate their temperature by placing different proportions of their bodies in sun or in shade. The variations are numerous, but the end result is the same ¡V some degree of temperature regulation in reptiles.
It lives its whole life above the northern tree line in the Arctic tundra, roaming across North America and Greenland but not extending into mainland Europe or Asia.
Acknowledgements: Slides of dead fish courtesy of OKDEQ. We would like to thank our students Trevor Nance Jr, and Matt Ward for their help in the laboratory sample preparations. We would also like to thank OKDEQ (Chris Armstrong) and EPA Region 6 (Rick McMillin) for their patience.
The habitat of the Arctic wolf is a very harsh place. The temperature must be below zero degrees. There are tundra, rolling hills, glacier valleys, ice fields, shallow lakes, and green flatlands (Arctic/Antarctic: The Arctic Wolf). These snowy white creators don’t have that many places to live. Arctic wolves used to be everywhere in North America, but sadly now they are reduced to Canada, Alaska, Idaho, Michigan, Minnesota, Montana, Wisconsin, and Wyoming (Arctic/Antarctic: The Arctic Wolf). Arctic wolves are one of the most dangerous types of wolves; people need to find a way to save them and their habitat before they disappear forever.
The fisheries management of the Lake Annecy stocked Arctic char Salvelinus alpinus fingerlings from different origins to improve the its catches.Different origions of stocked fish includes included catching progeny of wild spawning Arctic char from Lake Annecy and rearing the juveniles in the hatchery at Lake Annecy,, juveniles produced in a hatchery on Lake Geneva from eggs from wild fish in Lake Geneva, or using juveniles of a brood stock reared in the INRA research hatchery on Lake Geneva. The effectiveness of stocking, growth and dispersal after release of fingerlings of Arctic char from these different origins were studied for the fish stocked in 1997. Another experiment was start in 2001, to confirm the previous results on effectiveness and growth. The growth of wild Arctic char were not very much different from hatchery reared stock. The portion of wild fish in the catches is 50%. Juveniles produced from INRA captive brood stock were found more effective in the catch and also showed wider dispersal after stocking. Mean effectiveness of stocking is 14 %.
The Arctic Tundra The Tundra is located in the northern regions of North America, Europe, Asia, and Africa. as well as a few regions of Antarctica. The Tundra is the second largest vegetation. zone in Canada. It can be divided into three different sections: the High Arctic Tundra, the Low Arctic Tundra and the Alpine Tundra.
In 1758, a Swedish naturalist named Carolus Linneas gave the Atlantic salmon its scientific name, Salmo salar which Latin for “the leaper” (Atlantic Salmon Museum, 2014). Today, it still continues to be a well-known and vital part of oceans ecosystems. They are sometimes referred to as the ‘king of fish’ (The North Atlantic Salmon Conservation Organization, 2014).
Cold water is the key aspect in the phenomenon called the mammalian diving reflex. This reflex has been beneficially used for thousands of years by whales, dolphins, seals and other mammals that inhabit the frigid waters of the world. The diving reflex slows heart rate and causes peripheral vasoconstriction to keep blood and oxygen to the brain and other vital core organs. This reflex allows these mammals to conserve oxygen and stay submerged over longer periods of time, providing them more time for finding food, protection and travel.
The heavily armored jawless fish had many adaptations that permitted them to still move and hunt successfully. Can you postulate on the details of exactly how heavily armored jawless fish caught and ingested their prey without the mechanical advantages of a hinged jaw?
Arctic hares have unusual habits that help protect them from cold environment and predators. Sometimes they huddle in large groups, hundreds of them, keeping their bodies close together for warmth and it’s harder to attack if together. If a hungry wolf or arctic fox happens to surprise the group, the hares scatter into different directions and confuse their predators with their speed and numbers so they have a greater chance of surviving/getting away. At rest, arctic hares appear smaller than they actually are. They sit on their legs and flatten their ears to conserve their body heat. Unlike hares that live in warmer regions the Arctic Hare has relatively short ears; which have developed that way to limit its body's exposure to the cold.
Amblyopsis spelaea, the first cavefish species to be described in 1842, was also found to be blind (Juan, Guzik, Jaume, & Cooper, 2010). Today, biologists are carrying out numerous investigations on the Astyanax cavefish species, which have eye degenerative traits. The degree of functi...
Speciation and gene duplication followed by modifications are considered to be the primary events of genome evolution and were well recognized in the pre genomic era. The genes having a relationship of common descent are termed as homologs. The concept of orthology and paralogy were introduced by Walter Fitch in 1970 to distinguish between homologous genes according to their mode of descent. Orthologs are homologous genes related via vertical descent or speciation whereas paralogs are homologous genes originating through duplication in a certain lineage [1]. Paralogs can be further classified into outparalogs and inparalogs depending upon whether the gene duplication antedate or postdate the speciation event respectively [2].
Record, C.~F. Anderson and T.~M. Lohman, ‘Thermodynamic Analysis of Ion Effects on the Binding and Conformational Equilibria of Proteins and Nucleic Acids: The Roles of Ion Association or Release, Screening, and Ion Effects on Water Activity’, Q.~Rev.~Biophys., 11.June 1978 (1978), 103–78 .