Isolation and characterisation of sex-specific transcripts from Oesophagostomum dentatum by RNA arbitrarily-primed PCR.
In light of the lack of molecular data on the sexual differentiation, maturation and interaction of parasitic nematodes of livestock, the present study investigated sex-specific gene expression in the nodule worm, Oesophagostomum dentatum (Strongylida). Using the technique of RNA arbitrarily-primed polymerase chain reaction (RAP-PCR), 31 expressed sequence tags (ESTs) differentially-displayed between the sexes were cloned. Northern blot analysis proved ten ESTs to be expressed exclusively in males (adults and fourth-stage larvae), while two were expressed solely in female stages. None of the ESTs were expressed in infective third-stage larvae. Sequence analysis and subsequent database searches revealed two male-specific ESTs to have significant similarity to Caenorhabditis elegans (predicted) proteins, a protein containing an EGF-like cysteine motif and a serine/threonine phosphatase. Another two male-specific ESTs had similarity to non-nematode sequences. The two female-specific ESTs had similarity to vitellogenin-5 and endonuclease III (predicted) from C. elegans. The remaining ESTs had no similarity to any nucleic acid or protein sequences contained in the databases. The isolation and characterisation of sex-specific ESTs from O. dentatum provides a unique opportunity for studying the reproductive biology of parasitic nematodes at the molecular level, with a view toward novel approaches for parasite control.
Boag
P R
PR
Victorian Institute of Animal Science, 475 Mickleham Road, Vic. 3049, Attwood, Australia. peter.boag@nre.vic.gov.au
Newton
S E
SE
Hansen
N
N
Christensen
C M
CM
Nansen
P
P
Gasser
R B
RB
D000818:Animals; D015152:Blotting, Northern; D020224:Expressed Sequence Tags; D005260:Female; D020869:Gene Expression Profiling; D008297:Male; D008969:Molecular Sequence Data; D009814:Oesophagostomiasis / Q000469:parasitology; D009815:Oesophagostomum / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D016133:Polymerase Chain Reaction; D018510:RNA, Helminth / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D012727:Sex Characteristics; D013552:Swine / Q000469:parasitology; D014158:Transcription, Genetic
D018510:RNA, Helminth; D012333:RNA, Messenger