cDNA-AFLP analysis in levamisole-resistant Haemonchus contortus reveals alternative splicing in a nicotinic acetylcholine receptor subunit.
The cDNA-AFLP (cDNA-amplified fragment length polymorphism) method comparing transcripts from levamisole-resistant and susceptible Haemonchus contortus isolates has led to the successful identification of a number of potentially useful levamisole-resistance markers. In the present study, we report the characterization of the transcript-derived fragment (TDF) named HAX which was confirmed to be specifically expressed in three levamisole-resistant isolates by RT-PCR experiments. Cloning and sequencing of the full-length cDNA sequence of HAX revealed high similarity to the Caenorhabditis elegans acr-8 gene and its putative H. contortus orthologue encoding a nicotinic acetylcholine receptor subunit. This Hco-acr-8b short isoform corresponded to a spliced variant of Hco-acr-8 mRNA containing the two first exons and a part of intron 2. As nicotinic acetylcholine receptors constitute the pharmacological target of levamisole, Hco-acr-8b may potentially be involved in the molecular mechanisms leading to levamisole-resistance acquisition in H. contortus.
Fauvin
Aymeric
A
INRA, UR1282 Infectiologie Animale et Santé Publique, F-37380 Nouzilly, France.
Charvet
Claude
C
Issouf
Mohamed
M
Cortet
Jacques
J
Cabaret
Jacques
J
Neveu
Cédric
C
D017398:Alternative Splicing; D054458:Amplified Fragment Length Polymorphism Analysis; D000818:Animals; D000969:Antinematodal Agents / Q000494:pharmacology*; D017173:Caenorhabditis elegans / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D018509:DNA, Helminth / Q000737:chemistry / Q000235:genetics; D004351:Drug Resistance; D006189:Haemonchus / Q000187:drug effects* / Q000235:genetics*; D007978:Levamisole / Q000494:pharmacology*; D008969:Molecular Sequence Data; D021122:Protein Subunits; D011978:Receptors, Nicotinic / Q000096:biosynthesis* / Q000235:genetics*; D017422:Sequence Analysis, DNA; D017385:Sequence Homology
D000969:Antinematodal Agents; D018076:DNA, Complementary; D018509:DNA, Helminth; D021122:Protein Subunits; D011978:Receptors, Nicotinic; D007978:Levamisole