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Abstract: The activity of glycolytic enzymes and the expression levels of myosin RNA was monitored in the white muscle of juvenile spotted wolffish (Anarhichas minor) reared under different temperature regimes. [...]

Abstract Background The insulin signaling pathway (ISP) has a key role in major physiological events like carbohydrate metabolism and growth regulation. The ISP has been well described in vertebrates and in a few invertebrate model organisms but remains largely unexplored in non-model invertebrates. This study is the first detailed genomic study of this pathway in a crustacean species, Daphnia pulex. Results The Daphnia pulex draft genome sequence assembly was scanned for major components of the ISP with a special attention to the insulin-like receptor. Twenty three putative genes are reported. The pathway appears to be generally well conserved as genes found in other invertebrates are present. Major findings include a lower number of insulin-like peptides in Daphnia as compared to other invertebrates and the presence of multiple insulin-like receptors (InR), with four genes as opposed to a single one in other invertebrates. Genes encoding for the Dappu_InR are likely the result of three duplication events and bear some unusual features. Dappu_InR-4 has undergone extensive evolutionary divergence and lacks the conserved site of the catalytic domain of the receptor tyrosine kinase. Dappu_InR-1 has a large insert and lacks the transmembranal domain in the β-subunit. This domain is also absent in Dappu_InR-3. Dappu_InR-2 is characterized by the absence of the cystein-rich region. Real-time q-PCR confirmed the expression of all four receptors. EST analyses of cDNA libraries revealed that the four receptors were differently expressed under various conditions. Conclusions Duplications of the insulin receptor genes might represent an important evolutionary innovation in Daphnia as they are known to exhibit extensive phenotypic plasticity in body size and in the size of defensive structures in response to predation.

The article discusses a research which described a novel salmon gill poxvirus (SGPV) variant among Atlantic salmon in Eastern Canada. It attempts to isolate and identify the variant. It discusses the results of disease testing, quantitative polymerase chain reaction and transmission electron microscopy.

This is the first report of early-life developmental characteristics (coloration pattern, growth and survival) and genetic identification of the wolffish interspecific hybrid between Anarhichas minor and A. lupus, both endangered species in Canadian coastal water and of interest for cold-water aquaculture diversification. A first growth trial at 8 °C featuring pure strains A. minor and the hybrid A. minor × A. lupus in triplicates was conducted in 2006 during the period from 0 to 140 days post-hatch. A second growth trial was runned in 2007 featuring A. minor, A. lupus and the reciprocal hybrids A. minor × A. lupus and A. lupus × A. minor. Egg development indicators and early-hatching characteristics are reported. [ABSTRACT FROM AUTHOR]