title: Differential protein expression profile in the liver of pikeperch (Sander lucioperca) larvae fed with increasing levels of phospholipids.
abstract: A comparative proteomic approach was used to assess the protein expression profile in the liver of 34days old pikeperch larvae fed from day 10 post hatching, with three isoproteic and isolipidic formulated diets varying by their phospholipid (PL) contents (% dry diet weight): 1.4% (PL1), 4.7% (PL5) and 9.5% (PL9). Using 2D-DIGE minimal labelling of liver extracts, we were able to show 56 protein spots with a differential intensity (p<0.05) depending on the dietary PL content. Among these spots, 11 proteins were unambiguously identified using nanoLC-MS/MS tandem mass spectrometry. In the PL9 larvae, our results indicate that the glycolytic pathway could be down-regulated due to the under-expression of the fructose biphosphate aldolase B and the phosphoglucomutase 1. Meanwhile, propionyl coenzyme A carboxylase (a gluconeogenic enzyme) was under-expressed. In addition, another gluconeogenic and lipogenic enzyme, pyruvate carboxylase, was identified in 3 different spots as being under-expressed in fish fed with the intermediate PL level (PL5). A high PL content increased the expression of sarcosine dehydrogenase, an enzyme involved in methionine metabolism, along with vinculin, a structural protein. Moreover, several stress proteins (glutathione S-transferase M, glucose regulated protein 75 and peroxiredoxin-1) were modulated in response to the dietary PL level and fatty acid composition. In the larvae fed with the lowest dietary PL content (PL1), over-expression of both GSTM and GRP75 might indicate a cellular stress in this experimental treatment, while the under-expression of Prx1 might indicate a lower defence against oxidative stress. In conclusion, this nutriproteomic approach showed significant modifications of protein expression in the liver of pikeperch larvae fed different PL contents, highlighting the importance of these nutrients and their influence on metabolism processes and on stress response.
authors.affiliation: Institut National des Sciences et Technologies de la Mer, Salammbo, Tunisia. hamza.neila@gmail.com <hamza.neila@gmail.com>
authors.forename: Neïla
authors.initials: N
authors.lastname: Hamza
authors.forename: Frédéric
authors.initials: F
authors.lastname: Silvestre
authors.forename: Mohamed
authors.initials: M
authors.lastname: Mhetli
authors.forename: Ines Ben
authors.initials: IB
authors.lastname: Khemis
authors.forename: Marc
authors.initials: M
authors.lastname: Dieu
authors.forename: Martine
authors.initials: M
authors.lastname: Raes
authors.forename: Chantal
authors.initials: C
authors.lastname: Cahu
authors.forename: Patrick
authors.initials: P
authors.lastname: Kestemont
mesh_terms: D000818:Animals; D004041:Dietary Fats / Q000378:metabolism*; D029941:Fish Proteins / Q000235:genetics* / Q000378:metabolism; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D007814:Larva / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D010473:Perciformes / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism*; D040901:Proteomics
chemical_list: D004041:Dietary Fats; D029941:Fish Proteins; D010743:Phospholipids