A moderate increase in ambient temperature modulates the Atlantic cod (Gadus morhua) spleen transcriptome response to intraperitoneal viral mimic injection

• Published in: BMC Genomics
• Main Authors: Hori, Tiago S., Gamperl, A. Kurt, Booman, Marije, Nash, Gordon W., Rise, Matthew L.
• Format: Article in Journal/Newspaper
• Language: English
• Published: BioMed Central Ltd. 2012
• Subjects: QH426 Genetics; atlantic cod; Gadus morhua; Newfoundland
• Online Access: https://research.library.mun.ca/618/; https://research.library.mun.ca/618/1/moderate_increase_ambient_temp.pdf; https://research.library.mun.ca/618/3/moderate_increase_ambient_temp.pdf; https://doi.org/10.1186/1471-2164-13-431

Background Atlantic cod (Gadus morhua) reared in sea-cages can experience large variations in temperature, and these have been shown to affect their immune function. We used the new 20 K Atlantic cod microarray to investigate how a water temperature change which simulates that seen in Newfoundland during the spring-summer (i.e. from 10[DEGREE SIGN]C to 16[DEGREE SIGN]C, 1[DEGREE SIGN]C increase every 5 days) impacted the cod spleen transcriptome response to the intraperitoneal injection of a viral mimic (polyriboinosinic polyribocytidylic acid, pIC). Results The temperature regime alone did not cause any significant increases in plasma cortisol levels and only minor changes in spleen gene transcription. However, it had a considerable impact on the fish spleen transcriptome response to pIC [290 and 339 significantly differentially expressed genes between 16[DEGREE SIGN]C and 10[DEGREE SIGN]C at 6 and 24 hours post-injection (HPI), respectively]. Seventeen microarray-identified transcripts were selected for QPCR validation based on immune-relevant functional annotations. Fifteen of these transcripts (i.e. 88%), including DHX58, STAT1, IRF7, ISG15, RSAD2 and IkappaBalpha, were shown by QPCR to be significantly induced by pIC. Conclusions The temperature increase appeared to accelerate the spleen immune transcriptome response to pIC. We found 41 and 999 genes differentially expressed between fish injected with PBS vs. pIC at 10[DEGREE SIGN]C and sampled at 6HPI and 24HPI, respectively. In contrast, there were 656 and 246 genes differentially expressed between fish injected with PBS vs. pIC at 16[DEGREE SIGN]C and sampled at 6HPI and 24HPI, respectively. Our results indicate that the modulation of mRNA expression of genes belonging to the NF-kappaB and type I interferon signal transduction pathways may play a role in controlling temperature-induced changes in the spleen's transcript expression response to pIC. Moreover, interferon effector genes such as ISG15 and RSAD2 were differentially expressed between fish ...