SUMMARYWe investigated the effects of embryonic temperature (ET) treatments (22, 26 and 31°C) on the life-time recruitment of fast myotomal muscle fibres in zebrafish Danio rerio L. reared at 26/27°C from hatching. Fast muscle fibres were produced until 25 mm total length (TL) at 22°C ET, 28 mm TL at 26°C ET and 23 mm TL at 31°C ET. The final fibre number (FFN) showed an optimum at 26°C ET (3600) and was 19% and 14% higher than for the 22°C ET (3000) and 31°C ET (3100) Supplementary material available online at

Background: Stac3, an uncharacterised gene, was identified by its high expression levels in vertebrate muscle. Results: Knockdown of stac3 inhibited zebrafish myofibrillar protein assembly and differentiation in C2C12 cells by perturbing Akt signaling and cell cycle exit. Conclusion: Stac3 is a novel regulator of myogenic differentiation. Significance: Identifying new genes controlling myogenic differentiation will allow greater understanding of processes leading to muscular diseases.

The cee (conserved edge expressed protein) gene was recently identified in a genome-wide screen to discover genes associated with myotube formation in fast muscle of pufferfish. Comparative genomic analyses indicate that cee arose some 1.6-1.8 billion years ago and is found as a single-copy gene in most eukaryotic genomes examined. The complexity of its structure varies from an intronless gene in yeast and tunicates to nine exons and eight introns in vertebrates. cee is particularly conserved among vertebrates and is located in a syntenic region within tetrapods and between teleosts and invertebrates. Low dN/dS ratios in the cee coding region (0.02-0.09) indicate that the Cee protein is under strong purifying selection. In Atlantic salmon, cee is expressed in the superficial layers of developing organs and tissues. These data, together with functional screens in yeast and Caenorhabditis elegans, indicate that cee has a hitherto uncharacterized role in normal growth and development.

The accuracy and efficiency of marker-assisted selection (MAS) has been proven for economically critical aquaculture species. The potato grouper (Epinephelus tukula), a novel cultured grouper species in Taiwan, shows large potential in aquaculture because of its fast growth rate among other groupers. Because of the lack of genetic information for the potato grouper, the first transcriptome and expressed sequence tag (EST)-derived simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers were developed. Initially, the transcriptome was obtained from seven cDNA libraries by using the Illumina platform. De novo transcriptome of the potato grouper yielded 51.34 Gb and 111,490 unigenes. The EST-derived SSR and SNP markers were applied in genetic management, in parentage analysis, and to discover the functional markers of economic traits. The F1 juveniles were identified as siblings from one pair of parents (80 broodstocks). Fast- and slow-growth individuals were analyzed using functional molecular markers and through their association with growth performance. The results revealed that two SNPs were correlated with growth traits. The transcriptome database obtained in this study and its derived SSR and SNP markers may be applied not only for MAS but also to maintain functional gene diversity in the novel cultured grouper.

Mixed fisheries refer to fishing activities that catch more than one species simultaneously, and a species may be fished using different gear. A trawl fishery shares these features to exploit multiple species simultaneously, with diverse fishing gear and strategies. The situation becomes more complex when interactions among fleet dynamics, fishing activities, and fishery resources are involved and influence each other. Information regarding the operational patterns may be hidden in a set of long-term big data. This study aims to investigate the fishery structure and fleet dynamics of trawl fisheries in Taiwan for spatial planning and management, based on a long-term dataset from a management system that collects information by using voyage data recorders (VDR) and dockside observers. We applied a two-step data mining process with a clustering algorithm to classify the main groups of fishery resources and then identified 18 catch métiers based on catch composition. The target species, operation pattern, and fishing season were determined for each métier, and associated with the relevant fishery resources and the fishing gear used. Additionally, fishing effects on target species were estimated using information on fishing grounds and trajectories from VDR. The métier-based approach was successfully applied to define the six major fishery resources targeted by trawlers. We examined the key features of fishing activity associated with catch composition and spatial-temporal fishing metrics, which could be used to provide suggestions for the spatial planning and management of the mixed trawl fishery in the offshore waters of Taiwan.