title: A suite of genes expressed during transition to parasitic lifestyle in the trichostrongylid nematode Haemonchus contortus encode potentially secreted proteins conserved in Teladorsagia circumcincta.
abstract: The control of gastro-intestinal nematodes remains largely based on anthelminthic treatments, however spreading of anthelmintic resistance has reduced their efficacy. The genes involved in the transition to parasitic lifestyle could constitute targets of interest to develop alternative control strategies. In the trichostrongylid nematode Haemonchus contortus, we have used a SSH (Suppressive Subtractive Hybridization) based approach to generate two distinct subtracted cDNA libraries specifically enriched in cDNA expressed during the early parasitic fourth stage larvae L4 (5 days post-infection). A total of 200 clones were subjected to dot-blot experiments and 46 clones were selected for further characterization. The 46 corresponding expressed sequence tags (EST) were found to cluster into nine contigs. The corresponding full-length cDNA was obtained for all candidates. The genes encoding potentially secreted proteins were investigated in more detail. RT-PCR experiments confirmed their specific expression or over expression from the early L4 larvae to the adult stages and search for homologs in the trichostrongylid species T. circumcincta was performed in order to investigate whether they may be novel cross-specific targets.
authors.affiliation: French National Institute for Agricultural Research (INRA), UR1282 Infectiologie Animale et Santé Publique, F-37380 Nouzilly, France.
authors.forename: Alexia
authors.initials: A
authors.lastname: Delannoy-Normand
authors.forename: Jacques
authors.initials: J
authors.lastname: Cortet
authors.forename: Jacques
authors.initials: J
authors.lastname: Cabaret
authors.forename: Cédric
authors.initials: C
authors.lastname: Neveu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D005260:Female; D018507:Gene Expression Regulation, Developmental; D015723:Gene Library; D006189:Haemonchus / Q000235:genetics* / Q000378:metabolism*; D015801:Helminth Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D007814:Larva; D008297:Male; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D014251:Trichostrongyloidea / Q000235:genetics / Q000378:metabolism
chemical_list: D015801:Helminth Proteins