Unknown,Transcriptomics,Genomics,Proteomics

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Oligonucleotide microarray for Sparus aurata

ABSTRACT: This study describes the development and validation of the Aquagenomic Sparus aurata oligonucleotide-microarray (SAQ) based on the Agilent Technology system (eArray) to provide a platform for studies on the gene expression of gilthead seabream. The platform developed used all available public ESTs stored and annotated in the Aquagenomic Consortium seabream library (10K). In fish, lipopolysaccharide (LPS) gives a robust cytokine response that is stimulated by crude LPS preparations, some component of the LPS complex are responsible for this stimulation. Peptidoglycan (PGN) is a component of G-negative bacteria (found as a contaminant of crude LPS preparations) able to be recognized by macrophages inducing depth transcriptional modulations and a strong inflammatory response. For microarray analysis, head kidney macrophage cultures were used (N = 36 fish). Each cell culture was stimulated with equal concentrations of PGN and LPS from E. coli O111:B4 strain (10 ug/mL): non-stimulated cell cultures (control n = 9 fish), stimulated during 6 h with LPS (n = 9), and stimulated during 1 h (n = 9), and 6 h (n = 9) with PGN. A loop microarray design approach was used for the study. All experimental RNA samples were labelled with a single colour dye (Cy3) and each stimulated sample was compared to the control sample (pool without stimulation) labelled with the same dye (Cy3). Our microarray analyses identified differential transcriptional modulations in macrophages stimulated with both LPS and PGN at the level of differentially activated RNA transcripts related with the regulation of transcriptional program, prostaglandin synthesis or highlighting the expression of responsive gene-cassettes tightly related to LPS-PGN host recognition. A total of 43,398 oligonucleotide probes were used to construct a high-density seabream microarray based on the Agilent 4 × 44 K design format. Microarray hybridization validation was made by analyzing the gene expression profiles in primary cultures of seabream macrophages (MC). 7,285 transcripts with annotated sequences were spotted in triplicate onto the slide (total probes 21,855), as well as 8,377 ESTs without annotation, 183 enriched sequences (gene bank) with 15 replicated probes (total probes 2,745), and finally 1,417 internal control probes of Agilent (N = 43,398).

ORGANISM(S): Sparus aurata

SUBMITTER: Sebastian Boltana

PROVIDER: E-GEOD-28610 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Oligonucleotide microarray for Sparus aurata

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