Prioritised expression of stress-related proteins in environmental thermoadaptive responses of animals

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Underpinning the assumptions and models of how climate will affect natural populations are expectations of how the predicted temperature change affects the life history, fecundity, survival etc. of species in a given habitat, region or climatic zone. An important component of such models is knowledge of how well animal species can modify their bodies in response to persistent environmental signals, such as seasons or daily temperature fluctuations, and thereby to protect themselves from the debilitation by unexpected cold and heat snaps. Understanding the potential for protection requires an understanding of the fundamental mechanisms induced at the level of cell, tissue and whole body and which correlate with altered resistance to environmental stress.Research into how animals interact with their thermal environment has progressed enormously in the past 15 years. Advances in genomic science now offers 'globalised' measurement of thermal properties of animals, meaning simultaneous assessment of all of its constituent genes and proteins. This whole-system profiling has emerged as a key tool for analysing the properties and responses of biological systems, and the outcomes have informed many different areas of biology. But the technology continues to evolve and advance. Earlier techniques have given way to new approaches that give the whole picture, with more detail, faster, and for less cost. These new techniques, mainly based on very high-throughput DNA sequencing, have recently been adapted to provide many different kinds of information. One of these techniques allows us to quantify the number of proteins being made in tissues that are responding to sudden changes in their circumstances, such as temperature, and which improve the ability of animals to survive difficult times. Identifying the genes and proteins that respond tells us a lot about how the animal improves its life chances, when otherwise it might not survive. It also tells us which problems are caused by temperature shock and how these problems are resolved or mitigated.Our project will apply a new technique to this well-understood environmental problem, which is how a fish survives extreme cold snaps, which can be so severe in freshwater habitats that fish are killed, sometimes in large numbers. Yet, if the fish were given a 'taste' of cool waters signalling the likely occurrance of more extreme temperatures it can prepare its body and tissues such that extreme cold isn't so damaging. So we wish to define exactly what causes debilitation and death, and how the animals protects itself from extreme, debilitating cold by preconditioning to cool. But understanding the fundamental mechanisms operating in these animals will provide information of much broader significance. The responses to cold include genes and proteins working in most, if not all, animals, which gives them an ability to respond to stressors other than cold. A good example is how a cold shock protein in fish and hibernating mammals has been shown to protect the central nervous system in mouse models from disruption caused by neurodegenerative disease.We will extract tissues of the common carp before and after they have been cooled from a summer temperature to a winter temperature, and 'globally' measure the number and identity of thousands of new proteins created immediately after cooling. This new knowledge will point directly to responding genes and the proteins they encode. We will also focus on a particular group of genes whose proteins are already known to be highly expressed in the cold. We will test the idea that these proteins help protect the DNA and RNA of cells from structural imperfections caused by cold.