Modeling the efficacy of CRISPR gene drive for snail immunity on schistosomiasis control.

CRISPR gene drives could revolutionize the control of infectious diseases by accelerating the spread of engineered traits that limit parasite transmission in wild populations. Gene drive technology in mollusks has received little attention despite the role of freshwater snails as hosts of parasitic flukes causing 200 million annual cases of schistosomiasis. A successful drive in snails must overcome self-fertilization, a common feature of host snails which could prevents a drive's spread.

Live Imaging of Cleavage Variability and Vesicle Flow Dynamics in Dextral and Sinistral Spiralian Embryos.

Spiral cleavage is a mode of embryonic cell division found in species from several Phyla, including molluscs, annelids and flatworms. It reflects a tilting in the direction of spindle orientation and cell division at the 4 to 8-cell stage, which may be dextral or sinistral, and propagates into later organismal asymmetry. Genetic analysis in a small number of gastropod molluscs shows the direction of spiral cleavage is determined by maternal genotype, though whether this is also the case more generally for spiralians, and whether spiral cleavage at the 4-8 cell stage is preceded by earlier internal chirality in any spiralian species, is unknown.

Draft genome assemblies and predicted microRNA complements of the intertidal lophotrochozoans Patella vulgata (Mollusca, Patellogastropoda) and Spirobranchus (Pomatoceros) lamarcki (Annelida, Serpulida).

MicroRNAs (miRNA) are small non-coding RNAs that act post-transcriptionally to regulate gene expression levels. Some studies have indicated that microRNAs may have low homoplasy, and as a consequence the phylogenetic distribution of microRNA families has been used to study animal evolutionary relationships. Limited levels of lineage sampling, however, may distort such analyses.

The Lophotrochozoan TGF-β signalling cassette - diversification and conservation in a key signalling pathway.

TGF-β signalling plays a key role in the patterning of metazoan body plans and growth. It is widely regarded as a 'module' capable of co-option into novel functions. The TGF-β pathway arose in the Metazoan lineage, and while it is generally regarded as well conserved across evolutionary time, its components have been largely studied in the Ecdysozoa and Deuterostomia.

Right across the tree of life: the evolution of left-right asymmetry in the Bilateria.

Directional left/right (LR) asymmetries, in which there are consistent, heritable differences in morphology between the left and right sides of bilaterally symmetrical organisms, are found in animals across the Bilateria. For many years, we have lacked evidence for shared mechanisms underlying their development. This led to the supposition that the mechanisms driving establishment of LR asymmetries, and consequently the asymmetries themselves, had evolved separately in the three major Superphyla that constitute the Bilateria.

Functional conservation and divergence of BMP ligands in limb development and lipid homeostasis of holometabolous insects.

Bone morphogenetic protein (BMP) ligands play key roles in regulating morphological and physiological traits. To investigate how the functions of BMP ligands have evolved among insects, the roles of two key BMP ligands, decapentaplegic (dpp) and glass bottom boat (gbb), were studied in the flour beetle, Tribolium castaneum. RNA interference-mediated knockdown revealed that the role of dpp in establishing limb segmentation is conserved among insects.

The role of canonical Wnt signaling in leg regeneration and metamorphosis in the red flour beetle Tribolium castaneum.

Many organisms across the Metazoa have regenerative abilities with potentially conserved genetic mechanisms that can enlighten both medicine and evolutionary studies. Here, the role of canonical Wnt signaling was examined in the red flour beetle Tribolium castaneum in order to explore its role during metamorphosis and larval leg regeneration. Double-stranded RNA mediated silencing of Wnt-1 signaling resulted in a loss of wings and appendages with a dramatic reduction in width, indicating that the Wnt-1 signaling pathway is necessary for proper post-embryonic appendage development in T.