Trematomus

Abstract: A Comparison of Adaptive Radiations of Antarctic Fish with those of NonAntarctic Fish.- Age, Growth and Maximum Size of Antarctic Notothenioid Fish - Revisited.- Maternal Output in Polar Fish Reproduction.- Development, Dispersal and Recruitment: A Paradox for Survival Among Antarctic Fish.- The Pelagic Fish Community of the Polar Frontal Zone off the Kerguelen Islands.- Preliminary Investigations on the Evolution of the Tribe Electronini (Myctophiformes, Myctophidae).- Diversity of Digenea, Parasites of Fishes in Various Areas of the Antarctic.- Cold Adaptation and Stenothermy in Antarctic Notothenioid Fishes: What Has Been Gained and What Has Been Lost.- Do Antarctic Fish Respond to Heat Shock?.- Aspects of Eco-Physiological Adaptations in Antarctic Fish.- The Oxidative Metabolism of Antarctic Fish: Some Peculiar Aspects of Cold Adaptation.- Molecular Adaptation of Microtubules and Microtubule Motors from Antarctic Fish.- Metallothionein in Antarctic Fish.- Respiration and Activity of Arctic and Antarctic Fish with Different Modes of Life: A Multivariate Analysis of Experimental Data.- Antarctic Fish Immunoglobulins: Preliminary Data on Structure and Antibody Specificity.- Vascular Adaptations for a Low Pressure/High Flow Blood Supply to Locomotory Muscles of Antarctic Icefish.- Cardiac and Locomotory Muscle Mass in Antarctic Fishes.- Natriuretic Peptides in Antarctic Teleosts: Cardiac Receptors in Chionodraco hamatus and Trematomus bernacchii.- Atrial Natriuretic Peptides in Antarctic Fish.- Exercise in the Cold: High Energy Turnover in Antarctic Fish.- Ion and Metabolite Transport Through the Intestinal Luminal Membranes of the Antarctic Fish Trematomus bernacchii.- The Neuroendocrine System in the Intestinal Tract and Pancreas of Antarctic Fish.- Four Years in Notothenioid Systematics: A Molecular Perspective.- Chromosome Diversification in Antarctic Fish (Notothenioidei).- Phylogeny of the Channichthyidae (Notothenioidei, Teleostei) Based on Two Mitochondrial Genes.- Allozymic Polymorphism and Phylogeny of the Family Channichthyidae.- Origin and Mechanism of Evolution of Antifreeze Glycoproteins in Polar Fishes.- Evolution of Sensory Systems: A Comparison of Antarctic and Deep-Sea Ichthyofauna.- Molecular Adaptations in Antarctic Fish Hemoglobins.- Evolutionary Studies on Teleost Hemoglobin Sequences.

Abstract: Previous research on the Antarctic notothenioid fish Trematomus bernacchii demonstrated the loss of the heat shock response (HSR), a classical cellular defense mechanism against thermal stress, cha...

Abstract: The Antarctic fishes, isolated over evolutionary history in the sub-zero waters of the Southern Ocean, are an ideal group for studying the processes of cold adaptation One species of Antarctic notothenioid fish, Trematomus bernacchii, has lost the ability to induce heat shock proteins (Hsps) in response to exposure to acute thermal stress or to the toxic heavy metal cadmium, an important part of the cellular defense response to such stressors To elucidate the mechanism responsible for the lack of Hsp induction, we examined several stages of the hsp gene expression pathway, including transcription factor activity, Hsp70 mRNA production and protein synthesis patterns, in hepatocytes from T bernacchii Hsp70 mRNA was detected, as was heat shock factor 1 (HSF1) with DNA-binding activity However, exposure to elevated temperature and to chemical inducers of the heat shock response failed to increase Hsp70 mRNA levels, HSF1 activity or the concentration of any size class of Hsps These results suggest that Hsps, inducible in nearly every other species, are expressed constitutively in the cold-adapted T bernacchii

Abstract: During their many millions of years of evolution in the extreme and stable cold, Antarctic notothenioid fishes have acquired profoundly cold-adapted physiologies. Gene expression profiling via cDNA microarray was used to determine the extent to which one species of notothenioid, Trematomus bernacchii, has retained the ability to alter gene expression in response to heat stress. While an inability to up-regulate the expression of any size class of heat shock proteins (except for a 1.1-fold induction of the co-chaperone Hsp40) was observed, hundreds of additional genes, associated with a broad range of cellular processes, were responsive to heat. Many of these genes are associated with central aspects of the evolutionarily conserved cellular stress response (CSR), which plays a pivotal role in responding to physical and chemical stresses. The inability of T. bernacchii to mount a heat shock response underscores the potential susceptibility of this species to the effects of global warming.