1. Molecular and Functional Characterization of α Chain of Interleukin-15 Receptor (IL-15Rα) in Orange-Spotted Grouper (Epinephelus coioides) in Response to Vibrio harveyi Challenge.
- Author
-
Zhang, Yilin, Wu, Fan, Yang, Guanjian, Jian, Jichang, Lu, Yishan, and Wang, Zhiwen
- Subjects
- *
VIBRIO harveyi , *INTERLEUKIN-15 , *EPINEPHELUS , *IMMUNE response in fishes , *GROUPERS , *QUORUM sensing - Abstract
Simple Summary: In recent years, grouper industry has been severely devastated by vibriosis. The present study explored the function of IL-15Rα (α Chain of Interleukin-15 Receptor) response to Vibrio harveyi infection from mRNA and protein level, respectively. We concluded that: a) at the mRNA level, IL-15Rα was significantly upregulated in each tissue after V. harveyi infection of grouper, as well as in HKL cells after stimulated by pathogenic stimuli. b) at the protein level, IL-15Rα can increase the cytokine expression level and promote the proliferation of HKL cells, and can also improve the survival of groupers after V. harveyi infection. Our study contributes to a better understanding of the immune responses of Ec-IL15Rα (Epinephelus coioides IL15Rα) in preventing Vibrio infection in groupers. Interleukin-15 (IL15) is a proinflammatory cytokine that could induce the production of inflammatory cytokines. In this study, the α chain of the IL15 receptor of Epinephelus coioides (Ec-IL15Rα), a natural regulator of IL15, was identified, and immune response functions of fish were determined and characterized. Ec-IL15Rα contains a 720 bp open reading frame that encodes 239 amino acids, including four typical conserved cysteine residues with a highly conserved sushi domain. Ec-IL15Rα is closely related to Epinephelus lanceolatus and is the most clustered with teleost. Subcellular localization studies showed that Ec-IL15Rα was situated in the cytoplasm and cell membrane. Ec-IL15Rα was detected in 11 tissues, with the highest expression in the liver and blood. Meanwhile, the Ec-IL15Rα transcriptional levels substantially increased in nine tissues after Vibrio harveyi infection. Ec-IL15Rα was significantly up-regulated in HKLs by ConA, PHA, LPS and poly I:C stimulation. In vitro analysis, the recombinant protein of rEc-IL15Rα stimulates HKL proliferation and IL1R, IL6R, IL10, and IL16 expression. Challenge experiments revealed that IL15Rα protein showed an increase of 6.67–10% survival protection rate after V. harveyi infection. This study provides a better understanding of the immune protection of IL15Rα in vertebrate fish. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF