In addition to drug target discovery, our method highlights proteins participating in biological processes that are necessarily conserved across parasitic and free-living worms; in the case of B. malayi and the sequenced Caenorhabditids these processes span an evolutionary distance of 350 million years since their last common ancestor [11].
In this context, it is important to note that the three variants of S. mansoni TGR and the cytosolic and mitochondrial variants of E. granulosus are expressed in all the life cycle stages examined (cercariae, schistosomule and adult worms in the case of S. mansoni; larval worms, hydatid cyst wall and adult worms in the case of E. granulosus).
For most species of toxoglossans the prey is marine worms, but in the case of some larger cone snails, the prey is small fish.
Given that this function (despite giving rise to a weak Allee effect) is the primary cause of the occurrence of a worm breakpoint in the case of culicine filariasis, it is clear that better parameterization of this function and indeed better knowledge of worm mating behaviour in general will be required to fully address the impact of mating probabilities in filariasis transmission.
Taking a hint from Russian scientist Ivan Pavlov, famous for his early 20th-century experiments that taught dogs to associate food with the ringing of a bell, Princeton graduate student Amanda Kauffman trained worms to associate food -- in the case of C. elegans, bacteria are food -- with a chemical called butanone.
After perfusion, worms were counted and, in the case of 7 wk adults, separated on the basis of gender.
Between 80 and 250 L4 worms from the hermaphroditic species, or females in the case of gonochoristic species, were transferred onto NGM plates (∼30 worms per plate, yielding up to 10 replicates) seeded with OP50 for longevity assays and SL1344, PA01 and NCTC8532 for pathogen assays as food source.
The medians of the two prevalence distributions were 0.76% for the combined anopheline model-generated results and 0.23% for the culicine models, which supports previous theoretical results that worm breakpoints will be markedly higher in the case of anopheline compared to culicine filariasis [ 8].
L4 worms from the hermaphroditic species, and females in the case of gonochoristic species, were transferred onto NGM plates with OP50 that had been prewarmed to 37°.
One future task will be to investigate if the stilbonematid symbionts can be found only in the host habitat, as in the case of tube worms (Harmer et al. 2008) and lucinid mussels symbionts (Gros et al., 2003) or, instead, are widely distributed throughout the oceans and can survive without their hosts.
In the case of Ole Worm's collection, as in other cases, lack of interest among the owner's family after his death resulted in the transfer of the collection in 1655 to the royal cabinet in Copenhagen.
