Unknown,Transcriptomics,Genomics,Proteomics

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Specialized reaction to bacterial infection precedes antiviral innate immunity during development of teleost fish

ABSTRACT: During early stages of development, juvenile fish must rely on their innate immune system to defend against pathogens. At these early stages, the immune system is immature and is unlikely to express the full repertoire of genes that control defences. Although vulnerable, these larval fish can still fight of infections, indicating there are active defence mechanisms. Using rainbow trout as a model, we have taken a transcriptomics approach to determine the antibacterial (Aeromonas salmonicida) and antiviral (VHSV) responses to infection at four early life history stages, eyed egg, post-hatch, first feeding and three weeks post-first feeding. We performed microarray analysis using an Agilent 4x44K custom designed array, using a common RNA reference hybridization design. We show that all stages of the developing fish respond to the disease challenge at 3 days post-challenge, but the number and complexity of the response increases with developmental stage. Specifically, the response to virus at eyed egg and hatch stages does not show the full interferon response as is found at first feeding and 3 weeks post-first feeding. The experiments were carried out with a custom-designed Agilent (Agilent design ID: 028918) oligonucleotide microarray (A-MEXP-2315) named Trout_imm_v1. In total, 46 hybridisations were performed on individual animals, with 4 biological replicates per sampling point (apart from Bacteria infected eyed eggs for which two hybridizations were not used). This work was funded by the European Community’s seventh framework programme (FP7/2007-2013), under grant agreement no. 222719 (LIFECYCLE).

ORGANISM(S): Oncorhynchus mykiss

SUBMITTER: Sam Martin

PROVIDER: E-MTAB-3401 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Specialized reaction to bacterial infection precedes antiviral innate immunity during development of teleost fish

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