Genes coding for proteins involved in gene regulation and/or
development are of great interest in the study of the biology of
Schistosoma mansoni. This trematode is the etiologic agent of
schistosomiasis and presents a complex life cycle with drastic
morphologic changes between stages. Recently, some strains have become
resistant to the drugs currently in use to eradicate the disease. The
strategy of gene discovery program in S. mansoni by using the
EST (expressed sequence tag) approach has been very efficient in the
discovery of new S. mansoni genes, which were unlikely to be
identified using classical procedures based on phenotype. A class of
genes that interested us particularly were those that in other
organisms were known to be involved in the regulation of
embryogenesis. Among these, we selected one that presented a high
homology to a Drosophila gene named mago nashi. In diptera this
gene is involved in the process of germ plasm assembly and its
mutation results in sterility of F1 progeny and also in the formation
of the perpendicular axes. We reasoned that this gene might
conceivably play a role in the morphogenetic changes seen in the life
cycle of the parasite. We thus decided to characterize S.
mansoni mago nashi further by obtaining its full length
cDNA and genomic sequences, as well as studying its expression pattern
at the different life stages of the worm.
