Involvement of VAMP-2 in exocytosis of IL-1 beta in turbot (Scophthalmus maximus) leukocytes after Vibrio anguillarum infection

Biochem Biophys Res Commun. 2006 Apr 7;342(2):509-13. doi: 10.1016/j.bbrc.2006.01.138. Epub 2006 Feb 3.

Abstract

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Exocytosis / physiology*
  • Flatfishes*
  • Interleukin-1 / metabolism*
  • Leukocytes / metabolism*
  • Leukocytes / microbiology
  • Microscopy, Confocal
  • Molecular Sequence Data
  • Secretory Vesicles / metabolism
  • Secretory Vesicles / microbiology
  • Vesicle-Associated Membrane Protein 2 / biosynthesis
  • Vesicle-Associated Membrane Protein 2 / genetics
  • Vesicle-Associated Membrane Protein 2 / physiology*
  • Vibrio Infections / metabolism*
  • Vibrio Infections / microbiology

Substances

  • Interleukin-1
  • Vesicle-Associated Membrane Protein 2