DNA-binding activity in the excretory-secretory products of Trichinella pseudospiralis (Nematoda: Trichinelloidea)

Parasitology. 2001 Sep;123(Pt 3):301-8. doi: 10.1017/s0031182001008459.

Abstract

A novel DNA-binding peptide of Mr approximately 30 kDa was documented for the first time in the excretory-secretory (E-S) products of the infective-stage larvae of Trichinella pseudospiralis. Larvae recovered from muscles of infected mice were maintained for 48 h in DMEM medium. E-S products of worms extracted from the medium were analysed for DNA-binding activity by the electrophoretic mobility shift assay (EMSA). Multiple DNA-protein complexes were detected. A comparison of the Mr of proteins in the complexes indicated that they could bind to the target DNA as a dimer, tetramer or multiples of tetramers. Site selection and competition analysis showed that the binding has a low specificity. A (G/C-rich)-gap-(G/T-rich)-DNA sequence pattern was extracted from a pool of degenerate PCR fragments binding to the E-S products. Results of immunoprecipitation and electrophoretic mobility supershift assay confirmed the authenticity of the DNA-binding protein as an E-S product.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • Binding Sites
  • Binding, Competitive
  • DNA, Helminth / chemistry
  • DNA, Helminth / metabolism
  • DNA-Binding Proteins / chemistry
  • DNA-Binding Proteins / metabolism
  • DNA-Binding Proteins / physiology*
  • Electrophoresis, Gel, Two-Dimensional
  • Electrophoresis, Polyacrylamide Gel
  • Helminth Proteins / chemistry
  • Helminth Proteins / metabolism
  • Helminth Proteins / physiology*
  • Mice
  • Mice, Inbred ICR
  • Molecular Sequence Data
  • Molecular Weight
  • Poly dA-dT / metabolism
  • Polydeoxyribonucleotides / metabolism
  • Polymerase Chain Reaction
  • Precipitin Tests
  • Sequence Alignment
  • Sequence Analysis, DNA
  • Trichinella / chemistry
  • Trichinella / metabolism
  • Trichinella / physiology*

Substances

  • DNA, Helminth
  • DNA-Binding Proteins
  • Helminth Proteins
  • Polydeoxyribonucleotides
  • poly d(I-C)
  • Poly dA-dT