Molecular cloning, characterization and expression analysis of major histocompatibility complex class I alpha gene of pufferfish (Takifugu obscurus)

Abstract

The major histocompatibility complex (MHC) genes play a key role in immune response in vertebrates. In this study, an MHC I alpha homolog gene (PfMHC Ⅰα) from pufferfish (Takifugu obscurus) was identified and its subcellular localization and expression patterns of PfMHC Ⅰα after challenge in vivo and in vitro were analysed. The open reading frame of PfMHC Ⅰα was 1,089 bp in length, encoding 362 aa. The immunofluorescence result revealed that PfMHC Ⅰα was presented on the membrane of lymphocytes. qRT‐PCR analysis indicated that PfMHC Ⅰα was expressed in all examined tissues, with the highest expression in skin, followed by the expression in gills and whole blood. After challenge of Aeromonas hydrophila or polyinosinic: polycytidylic acid (Poly I:C) in vitro, the expression levels of PfMHC Ⅰα on pufferfish kidney lymphocytes were significantly up‐regulated, with the highest expression level at 48 hr post‐challenge. After infection with A. hydrophila or Poly I:C in vivo, the expression levels of PfMHC Ⅰα in the skin, whole blood and kidneys were significantly up‐regulated. Taken together, it is speculated that PfMHC Ⅰα associates with resistance to both intracellular and extracellular antigens and plays an important role in the host response against pathogen infection in pufferfish.

Major histocompatibility complex class IIα and IIβ of pufferfish (Takifugu obscurus): Identification and functional characterization in response to bacterial challenge

“…In this study, both of them were used to stimulate the lymphocytes of pufferfish, causing the up‐regulation of Pf‐MHC IIα and Pf‐MHC IIβ expression (Figure 7). This finding is consistent with the MHC I expression trend of pufferfish lymphocytes stimulated by pathogens (Fu et al, 2020b), and the trend of MHC IIα expression in Ayu ( Plecoglossus altivelis ) stimulated by pathogens (Li, Ding, et al, 2018; Li, Jiang, et al, 2018). The results suggested that MHC II in pufferfish not only participated in the presentation of endogenous antigens, but also was involved in presentation of exogenous antigens.…”

“…The pufferfish is anadromous and distribute in East China Sea, Yellow Sea and Sea of Japan with considerable economic value (Fu, Liu, et al, 2020). In recent years, bacterial diseases have brought a negative impact on the aquaculture industry, including the Gram‐negative bacterium A. hydrophila , the main pathogen of pufferfish (Fu et al, 2019).…”

Functional characterization of TNF‐α in pufferfish (Takifugu obscurus) in immune response and apoptosis against Aeromonas hydrophila

“…To understand the relative expression after A. hydrophila infection in vivo, the A. hydrophila (BYK00810) was cultured (Fu et al., 2020). Pufferfish were injected intraperitoneally (i.p.)…”

Effects on grass carp ( Ctenopharyngodon idella ) induced by waterborne lead exposure and the association with alteration of microbiota in the intestine and water

“…The total RNA from all samples was extracted with Trizol reagent (Vazyme, China) (Fu et al, 2020), and its quality and concentration were detected using electrophoresis in 1% agarose gel and NanoDrop 2000 spectrophotometer (NanoDrop Technologies, USA) (Kong et al, 2021). Next, RNA was reversely transcribed to cDNA using PrimeScript® RT reagent Kit with gDNA Eraser (Takara, Japan).…”

“…The β-actin of grass carp was used as housekeeping genes. The target and housekeeping genes were calculated using the 2 −ΔΔCT method (Fu et al, 2020).…”