Hormones and nuclear receptors in schistosome development

A substantial but disparate body of evidence suggests that hormones affect the development of schistosomes within their definitive hosts. Here, Raymon d Pierce and colleagues review such evidence for host steroid and thyroid h ormones, and for ecdysteroids, and link this to the expanding knowledge of the nuclear receptors for these hormones. Phylogenetic analysis of the nucl ear receptor superfamily and the characterization of the first schistosome nuclear receptors suggest that steroids and thyroid hormone probably act in directly, or by pathways not involving the control of gene transcription. H owever, the probability that schistosome nuclear receptors exist for a vari ety of unique ligands opens up exciting possibilities for targeted drug dev elopment.