Research article

Microarray analysis of gene expression induced by sexual contact in Schistosoma mansoni

Michael Waisberg^1,2 , Francisco P Lobo¹ , Gustavo C Cerqueira^2,3 , Liana KJ Passos⁴ , Omar S Carvalho⁴ , Glória R Franco¹ and Najib M El-Sayed^5,2

¹Laboratório de Genética Bioquímica, Departmento de Imunologia e Bioquímica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil

²Department of Parasite Genomics, The Institute for Genomic Research, Rockville, MD, USA

³Laboratório de Genética Molecular de Tripanosomatídeos, Departamento de Imunologia e Bioquímica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil

⁴Centro de Pesquisas René Rachou, Fundação Osvaldo Cruz, Belo Horizonte, MG, Brazil

⁵Department of Cell Biology and Molecular Genetics and Center for Bioinformatics and Computational Biology, University of Maryland, College Park, MD, USA

author email corresponding author email

BMC Genomics 2007, 8:181doi:10.1186/1471-2164-8-181

Published:	20 June 2007

Abstract

Background

The parasitic trematode Schistosoma mansoni is one of the major causative agents of Schistosomiasis, a disease that affects approximately 200 million people, mostly in developing countries. Since much of the pathology is associated with eggs laid by the female worm, understanding the mechanisms involved in oogenesis and sexual maturation is an important step towards the discovery of new targets for effective drug therapy. It is known that the adult female worm only develops fully in the presence of a male worm and that the rates of oviposition and maturation of eggs are significantly increased by mating. In order to study gene transcripts associated with sexual maturation and oviposition, we compared the gene expression profiles of sexually mature and immature parasites using DNA microarrays.

Results

For each experiment, three amplified RNA microarray hybridizations and their dye swaps were analyzed. Our results show that 265 transcripts are differentially expressed in adult females and 53 in adult males when mature and immature worms are compared. Of the genes differentially expressed, 55% are expressed at higher levels in paired females while the remaining 45% are more expressed in unpaired ones and 56.6% are expressed at higher levels in paired male worms while the remaining 43.4% are more expressed in immature parasites. Real-time RT-PCR analysis validated the microarray results. Several new maturation associated transcripts were identified. Genes that were up-regulated in single-sex females were mostly related to energy generation (i.e. carbohydrate and protein metabolism, generation of precursor metabolites and energy, cellular catabolism, and organelle organization and biogenesis) while genes that were down-regulated related to RNA metabolism, reactive oxygen species metabolism, electron transport, organelle organization and biogenesis and protein biosynthesis.

Conclusion

Our results confirm previous observations related to gene expression induced by sexual maturation in female schistosome worms. They also increase the list of S. mansoni maturation associated transcripts considerably, therefore opening new and exciting avenues for the study of the conjugal biology and development of new drugs against schistosomes.