Involvement of VAMP-2 in exocytosis of IL-1 beta in turbot (Scophthalmus maximus) leukocytes after Vibrio anguillarum infection.
Vibrio anguillarum is a major pathogen threatening the fish aquaculture in China. Infection of cultivated turbot (Scophthalmus maximus) with V. anguillarum induced rapid synthesis and secretion of IL-1beta, which initiates the innate immune response. SNARE proteins are known to regulate vesicular trafficking and fusion in all eukaryotes. Here, we determined whether SNARE proteins, specifically vesicle-associated membrane protein-2 (VAMP-2), are involved in regulated exocytosis of IL-1beta of leukocytes in marine fish. We show that VAMP-2 is present in turbot blood leukocytes, with nucleotide sequence identity of 88.2% and 93.0% to those of zebra fish and sea bass, respectively. After Vibrio infection, turbot leukocyte VAMP-2 was increased at the levels of transcription and translation in a temporal pattern coinciding with leukocyte IL-1beta secretion. Confocal microscopy localized VAMP-2 to vesicle structures in leukocytes. Taken together, our results suggest that VAMP-2 is involved in regulated exocytosis of cytokines in immunocytes in fish.
Department of Life Science, Ocean University of China, Qingdao 266003, China.
Yingmei
Y
Chai
Xiaohang
X
Huang
Bailin
B
Cong
Shenghao
S
Liu
Kui
K
Chen
Guangyou
G
Li
Herbert Y
HY
Gaisano
D000595:Amino Acid Sequence; D000818:Animals; D005089:Exocytosis / Q000502:physiology*; D005412:Flatfishes; D007375:Interleukin-1 / Q000378:metabolism*; D007962:Leukocytes / Q000378:metabolism* / Q000382:microbiology; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D022142:Secretory Vesicles / Q000378:metabolism / Q000382:microbiology; D050988:Vesicle-Associated Membrane Protein 2 / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D014735:Vibrio Infections / Q000378:metabolism* / Q000382:microbiology
D007375:Interleukin-1; D050988:Vesicle-Associated Membrane Protein 2