Towards the gene-based characterisation of maraena whitefish (Coregonus maraena) in local aquaculture

The present study provides a first overview of the developmental, physiological, and molecular mechanisms occurring in maraena whitefish in response to culturing procedures and to aquaculture related stressors. Maraena whitefish was found to be a suitable fish species for the establishment of a local, economic and sustainable aquaculture. However, it was shown that the stocking density, the temperature, and the water quality (reagarding pathogenic contaminations) must be carefully adjusted within optimal ranges, to avoid adverse effects on this sensitive species.Diese Arbeit gibt einen ersten Überblick der Entwicklung und der physiologischen und molekularen Mechanismen, welche im Ostseeschnäpel als Reaktion auf die Kultivierung und auf aquakulturrelevante Stressoren ablaufen. Der Ostseeschnäpel erwies sich als eine geeignete Fischart für die Etablierung einer lokalen, ökonomischen und nachhaltigen Aquakultur. Jedoch konnte gezeigt werden, dass die Besatzdichte, Temperatur und Wasserqualität (in Bezug auf Krankheitserreger) sorgfältig angepasst werden müssen, um negative Auswirkungen auf diese sensible Fischart zu vermeiden

Gradual and Acute Temperature Rise Induces Crossing Endocrine, Metabolic, and Immunological Pathways in Maraena Whitefish (Coregonus maraena)

The complex and still poorly understood nature of thermoregulation in various fish species complicates the determination of the physiological status on the basis of diagnostic marker genes and indicative molecular pathways. The present study aimed to compare the physiological impacts of both gradual and acute temperature rise from 18 to 24°C on maraena whitefish in aquaculture. Microarray-based transcriptome profiles in the liver, spleen and kidney of heat-stressed maraena whitefish revealed the modulation of a significantly higher number of genes in those groups exposed to gradually rising temperatures compared with the acutely stressed groups, which might reflect early adaptation mechanisms. Moreover, we suggest a common set of 11 differentially expressed genes that indicate thermal stress induced by gradual or acute temperature rise in the three selected tissues. Besides the two pathways regulated in both data sets unfolded protein response and aldosterone signaling in epithelial cells, we identified unique tissue- and stress type-specific pathways reflecting the crossroads between signal transduction, metabolic and immunologic pathways to cope with thermal stress. In addition, comparing lists of differentially regulated genes with meta-analyzed published data sets revealed that “acute temperature rise”-responding genes that encode members of the HSP70, HSP90, and HSP40 families; their functional homologs; co-chaperones and stress-signal transducers are well-conserved across different species, tissues and/or cell types and experimental approaches

Transcriptome sequencing of maraena whitefish (Coregonus maraena)

Maraena whitefish (Coregonus maraena, Bloch, 1779) is a high-quality food fish belonging to the family Salmonidae with considerable economic relevance in the Baltic area. Aquaculture of this species is fundamental for its successful conservation and thus sustainable fisheries. Robust fishes obtained from breeding lines build the basis for effective aquaculture. Doubtless, the utilization of transcriptome sequencing and identification of genetic markers contribute to this aim. 454 FLX Titanium Sequencing provided 1.31 million sequence reads representing a first insight into the C. maraena transcriptome. The 454 Newbler Assembly arranged 29,094 contigs with an average length of 798 bp. We found a whole series of transcripts highly probably resulting from ancient genome duplication and annotated 2887 different transcripts with an average length of 812 bp. Functional annotation obtained a transcript composition predominantly comprising enzyme-coding genes

Image_1_Gradual and Acute Temperature Rise Induces Crossing Endocrine, Metabolic, and Immunological Pathways in Maraena Whitefish (Coregonus maraena).PDF

<p>The complex and still poorly understood nature of thermoregulation in various fish species complicates the determination of the physiological status on the basis of diagnostic marker genes and indicative molecular pathways. The present study aimed to compare the physiological impacts of both gradual and acute temperature rise from 18 to 24°C on maraena whitefish in aquaculture. Microarray-based transcriptome profiles in the liver, spleen and kidney of heat-stressed maraena whitefish revealed the modulation of a significantly higher number of genes in those groups exposed to gradually rising temperatures compared with the acutely stressed groups, which might reflect early adaptation mechanisms. Moreover, we suggest a common set of 11 differentially expressed genes that indicate thermal stress induced by gradual or acute temperature rise in the three selected tissues. Besides the two pathways regulated in both data sets unfolded protein response and aldosterone signaling in epithelial cells, we identified unique tissue- and stress type-specific pathways reflecting the crossroads between signal transduction, metabolic and immunologic pathways to cope with thermal stress. In addition, comparing lists of differentially regulated genes with meta-analyzed published data sets revealed that “acute temperature rise”-responding genes that encode members of the HSP70, HSP90, and HSP40 families; their functional homologs; co-chaperones and stress-signal transducers are well-conserved across different species, tissues and/or cell types and experimental approaches.</p