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Comparative Transcriptome Analysis Reveals Ectopic Delta-5 and Delta-6 Desaturases Enhance Protective Gene Expression Upon Vibrio Vulnificus Challenge in Tilapia (Oreochromis Niloticus)

Overview
Journal BMC Genomics
Publisher Biomed Central
Specialty Genetics
Date 2021 Mar 23
PMID 33752587
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Abstract

Background: Tilapia (Oreochromis niloticus) cultures are frequently infected by Vibrio vulnificus, causing major economic losses to production units. Previously, tilapia expressing recombinant delta-5 desaturase and delta-6 desaturase (D56) were found to be resistant to V. vulnificus infection. In this report, we profile the D56-mediated molecular changes underlying this resistance in tilapia. A comparative transcriptome analysis was performed on V. vulnificus-infected wild-type and D56-transgenic tilapia using Illumina's sequencing-by-synthesis approach. Gene enrichment analysis on differentially expressed unigenes was performed, and the expression patterns were validated by real-time PCR.

Results: Comparative transcriptome analysis was performed on RNA-sequence profiles obtained from wild-type and D56-transgenic tilapia at 0, 6 and 24 h post-infection with V. vulnificaus. GO and KEGG gene enrichment analyses showed that D56 regulates several pathways and genes, including fatty acid (FA) metabolism associated, and inflammatory and immune response. Expression of selected FA metabolism-associated, inflammatory and immune responsive genes was validated by qPCR. The inflammatory and immune responsive genes that are modulated by FA-associated D56 likely contribute to the enhanced resistance against V. vulnificus infection in Tilapia.

Conclusions: Transcriptome profiling and filtering for two-fold change variation showed that 3795 genes were upregulated and 1839 genes were downregulated in D56-transgenic tilapia. These genes were grouped into pathways, such as FA metabolism, FA elongation, FA biosynthesis, biosynthesis of unsaturated FA, FA degradation, inflammation, immune response, and chemokines. FA-associated genes and immune-related genes were modulated by D56 at 6 h and 24 h post infection with V. vulnificus. The expression patterns of FA-related genes, inflammatory genes, antimicrobial peptide genes and immune responsive genes at 0, 3, 6, 12, 24 and 48 h post-infection suggests these genes are involved in the enhanced resistance of D56 transgenic tilapia to V. vulnificus.

References
1.
Hardardottir I, Kinsella J . Increasing the dietary (n-3) to (n-6) polyunsaturated fatty acid ratio increases tumor necrosis factor production by murine resident peritoneal macrophages without an effect on elicited peritoneal macrophages. J Nutr. 1992; 122(10):1942-51. DOI: 10.1093/jn/122.10.1942. View

2.
OHalloran D . fastQ_brew: module for analysis, preprocessing, and reformatting of FASTQ sequence data. BMC Res Notes. 2017; 10(1):275. PMC: 5508660. DOI: 10.1186/s13104-017-2616-7. View

3.
Rao X, Huang X, Zhou Z, Lin X . An improvement of the 2ˆ(-delta delta CT) method for quantitative real-time polymerase chain reaction data analysis. Biostat Bioinforma Biomath. 2015; 3(3):71-85. PMC: 4280562. View

4.
Altamura S, Kessler R, Grone H, Gretz N, Hentze M, Galy B . Resistance of ferroportin to hepcidin binding causes exocrine pancreatic failure and fatal iron overload. Cell Metab. 2014; 20(2):359-67. DOI: 10.1016/j.cmet.2014.07.007. View

5.
Thurman C, Rasmussen S, Prestia K . Effect of 3 Euthanasia Methods on Serum Yield and Serum Cortisol Concentration in Zebrafish (). J Am Assoc Lab Anim Sci. 2019; 58(6):823-828. PMC: 6926401. DOI: 10.30802/AALAS-JAALAS-18-000144. View