PUBLICATION

Phosvitin plays a critical role in the immunity of zebrafish embryos via acting as a pattern recognition receptor and an antimicrobial effector

Authors
Wang, S., Wang, Y., Ma, J., Ding, Y., and Zhang, S.
ID
ZDB-PUB-110519-11
Date
2011
Source
The Journal of biological chemistry   286(25): 22653-64 (Journal)
Registered Authors
Keywords
antimicrobial peptides, embryo, mutant, protein purification, zebrafish, antimicrobial activity, embryogenesis, phosvitin, vitellogenin, zebra fish
MeSH Terms
  • Amino Acid Sequence
  • Amino Acid Substitution
  • Animals
  • Anti-Infective Agents/chemistry
  • Anti-Infective Agents/metabolism
  • Anti-Infective Agents/pharmacology
  • Bacteria/drug effects
  • Embryo, Nonmammalian/immunology*
  • Embryo, Nonmammalian/metabolism
  • Embryo, Nonmammalian/microbiology*
  • Inhibitory Concentration 50
  • Ligands
  • Molecular Sequence Data
  • Ovum/metabolism
  • Phosvitin/chemistry
  • Phosvitin/genetics
  • Phosvitin/metabolism*
  • Phosvitin/pharmacology
  • Receptors, Pattern Recognition/chemistry
  • Receptors, Pattern Recognition/genetics
  • Receptors, Pattern Recognition/metabolism*
  • Sequence Deletion
  • Zebrafish/immunology*
  • Zebrafish/metabolism
  • Zebrafish/microbiology*
  • Zebrafish Proteins/chemistry
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism*
  • Zebrafish Proteins/pharmacology
PubMed
21531722 Full text @ J. Biol. Chem.
Abstract
How fish embryos that develop externally survive microbial attacks is poorly understood. Here we clearly demonstrated that the embryo extract of zebrafish and its early embryo both displayed antimicrobial activity against microbes including pathogenic Aeromonas hydrophila, and phosvitn (Pv), a nutritional protein abundant in eggs, was related to this antimicrobial activity. We also showed that recombinant Pv (rPv) acted as a pattern recognition receptor capable of recognizing the microbial signature molecules LPS, lipoteichoic acid and peptidoglycan as well as binding Gram-negative and positive microbes Escherichia coli, A. hydrophila and Staphylococcus aureus, and functioned as an antimicrobial agent capable of killing the microbes. Furthermore, we revealed that its C-terminal 55 residues (Pt5) with the functional sites Arg242 and Ala201/Ile203 were indispensable for Pv antimicrobial activity. Importantly, microinjection of rPv or Pt5 into early embryos significantly enhanced their resistance to A. hydrophila challenge, and this enhanced bacterial resistance was markedly reduced by co-injection of anti-Pv antibody plus rPv (or Pt5), but not by injection of anti-actin antibody plus rPv. Moreover, the generated mutants with in vitro antimicrobial activity, when injected into the embryos, could also promote their resistance to A. hydrophila, but those without in vitro antimicrobial activity could not. It is thus proposed that Pv participates in the protection of early embryos against pathogenic attacks via binding and disrupting potential pathogens. This work also opens a new way for the study of the immunological roles of yolk proteins in oviparous animals which rely on yolk proteins for embryonic development.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping