TRAF3 of blunt snout bream participates in host innate immune response to pathogenic bacteria via NF-κB signaling pathway. Issue 104 (September 2020)

• Record Type: Journal Article
• Authors: Lv, Yina; Xu, Qian; Mao, Ying; Xu, Yandong; Zhang, Ru; Zhong, Huan; Zhou, Yi; Xiao, Jun; Du, Mengke; Song, Huiyang; Liang, Yinhua; Yan, Jinpeng
• Is Part Of: Fish & shellfish immunology. Issue 104(2020)
• Page Start: 592
• Page End: 604
• Publication Date: 2020-09
• Subjects: TRAF3 -- Megalobrama amblycephala -- Innate immune -- Pathogenic bacteria -- NF-κB; Fishes -- Immunology -- Periodicals; Shellfish -- Immunology -- Periodicals; Poissons -- Immunologie -- Périodiques; Crustacés -- Immunologie -- Périodiques; 571.9617
• DOI: 10.1016/j.fsi.2020.06.022
• Languages: English
• ISSNs: 1050-4648

Abstract

Abstract: Tumor necrosis factor receptor-associated factor 3 (TRAF3) is a multifunctional adaptor protein primarily involved in both bacterial defense and antiviral immunity in living organisms. However, the knowledge on TRAF3 in blunt snout bream ( Megalobrama amblycephala ), a freshwater fish with economic values, remained unclear. In the present study, we identified and characterized successfully Traf3 gene from M . amblycephala ( maTraf3 ). The maTraf3 cDNA contained a 1722 bp open reading frame that encoded a protein of 573 amino acid residues. The deduced amino acid sequence comprised of a RING finger domain, two zinc finger motifs, a coiled-coil region and a MATH domain. Analysis of the transcriptional patterns of maTraf3 revealed that it was ubiquitously distributed in various tissues tested from M . amblycephala, with the abundance of expression in spleen and muscle. Following a challenge with Aeromonas hydrophila and lipopolysaccharide stimulation, the expression of maTraf3 was strongly enhanced at different time points in vitro and in vivo . MaTRAF3 was identified as a cytosolic protein and suggested to form aggregates or be associated with vesicles scattering in the cytoplasm. NF-κB transcription was activated by maTraf3 in reporter assay. The overexpression of maTraf3 produced high levels of pro-inflammatory cytokines such as IL-1β, IL-6, IL-8 and TNF-α, implying its immune-regulatory role in M . amblycephala . Taken together, our results obtained in this study demonstrated the crucial role of maTraf3 in mediating host innate immune response to pathogen invasion via NF-κB signaling pathway, which might indicate a novel therapeutic approach to combat bacterial infection in fish. Highlights: MaTraf3 gene was cloned and identified in M . amblycephala . MaTraf3 expression was enhanced after LPS stimulation and A . hydrophila challenge . MaTraf3 raised the mRNA levels of pro-inflammatory cytokines. MaTraf3 plays the crucial role in antibacterial immunity via NF-κB signaling pathway.