Transcription profiles for two key gender-specific gene families in Oesophagostomum dentatum during development in vivo and in vitro

In strongylid roundworms, such as Oesophagostomum dentatum (porcine nodule worm), some sex-specific genes are likely to be associated with parasite maturation, development and reproduction. In this study, an analysis of transcription of the two sex-specific genes (vit and msp) encoding vitellogenin and major sperm protein of O. dentatum, respectively, revealed that adult females transcribed vit and adult males msp at high levels, in contrast to immature larval stages and pre-adult worms from in vitro cultures for which no transcription of vit or msp was detected. The analysis showed that neither presence nor absence of the heterologous sex, nor the duration of infection, was central to vit or msp transcription. In small or “virgin” adults, no or only low-level transcription of vit and msp was detectable. We hypothesize that the transcription of the sex-specific genes is linked to endogenous factors, such as size, maturation of the reproductive organs and/or fitness of the worms, and not to exogenous influences. The maturation of worms appears to be linked, to some extent, to the expression of the genes studied herein.

► Transcription analysis of vit and msp was performed in Oesophagostomum dentatum. ► Females transcribe vit and males msp independent of infection duration or presence of the opposite sex. ► Larval stages or pre-adult worms cultured in vitro did not transcribe vit and msp. ► No/low transcription was detectable in small worms. ► Transcription might be linked to endogenous factors (size, maturation of the reproductive organs, fitness).