The Echinococcus granulosus antigen B shows a high degree of genetic variability

Exp Parasitol. 2004 Sep-Oct;108(1-2):76-80. doi: 10.1016/j.exppara.2004.07.009.

Abstract

Echinococcus granulosus larvae secret a polymeric lipoprotein known as antigen B (AgB) into the metacestode hydatid fluid. Three similar AgB subunits have been previously identified (AgB1, AgB2, and AgB3), and their respective genes isolated, but the actual number of genes encoding AgB subunits remains uncertain. In this study, we characterize the variability of genes encoding the AgB2 subunit, using PCR and RT-PCR followed by cloning and sequencing. We have analyzed 32 cDNA and 34 genomic sequences from a single metacestode, showing a high degree of sequence polymorphism. In addition, we have identified a possibly new AgB subunit, which we call AgB4. Additionally, we describe an AgB2 genomic clone lacking (i) a segment corresponding to the intron and (ii) a short, 45 bp sequence within exon II. The 45 bp segment encompasses the conserved splicing signals and corresponds to a highly conserved insect promoter motif.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Antigens, Helminth / genetics
  • Antigens, Surface / genetics
  • Base Sequence
  • Cloning, Molecular
  • DNA, Complementary / chemistry
  • DNA, Helminth / chemistry
  • Echinococcus granulosus / genetics*
  • Echinococcus granulosus / immunology*
  • Genetic Variation*
  • Helminth Proteins / genetics*
  • Lipoproteins / genetics*
  • Molecular Sequence Data
  • Polymerase Chain Reaction
  • RNA, Messenger / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Alignment

Substances

  • Antigens, Helminth
  • Antigens, Surface
  • DNA, Complementary
  • DNA, Helminth
  • Helminth Proteins
  • Lipoproteins
  • RNA, Messenger
  • antigen B, Echinococcus

Associated data

  • GENBANK/AY314984
  • GENBANK/AY314985
  • GENBANK/AY314986
  • GENBANK/AY314987
  • GENBANK/AY314988
  • GENBANK/AY314989
  • GENBANK/AY314990
  • GENBANK/AY314991
  • GENBANK/AY357108
  • GENBANK/AY357109
  • GENBANK/AY357110
  • GENBANK/AY357111
  • GENBANK/AY357112
  • GENBANK/AY357113
  • GENBANK/AY357114
  • GENBANK/AY357115
  • GENBANK/AY357116