Genetic population structure of the eight-barbel loach Lefua echigonia in the Ise Bay region,a single paleo-river basin in central Honshu,Japan

Ichthyological Research - We examined the genetic population structure of Lefua echigonia in the Ise Bay region based on the nucleotide sequences of the mitochondrial DNA cytochrome b region....     

The little dragon sculpinBlepsias cirrhosus,another case of internal gametic association and external fertilization

In the copulating cottid species,Blepsias cirrhosus, the point at which fertilization occurred was determined experimentally. Ovulated eggs were obtained directly from the ovary of impregnated females. Eggs maintained in ovarian fluid did not show any signs of development, whereas most of the eggs which had been placed in seawater had developed to the 4-cell stage after 24hrs. The eggs kept in ovarian fluid initiated segmentation when later transferred into seawater. Histological examination showed that a number of spermatozoa had entered the micropyle, but that penetration did not occur in eggs that were not immersed in seawater. In these eggs, the metaphase spindle of the second meiotic division was observed in the ooplasm, at the animal pole. These results indicate that, in impregnated females, the spermatozoa associate with the eggs in the ovarian cavity, but that fertilization occurs externally when the eggs are spawned.     

Pocket detection and interaction-weighted ligand-similarity search yields novel high-affinity binders for Myocilin-OLF,a protein implicated in glaucoma

Traditional structure and ligand based virtual screening approaches rely on the availability of structural and ligand binding information. To overcome this limitation, hybrid approaches were developed that relied on extraction of ligand binding information from proteins sharing similar folds and hence, evolutionarily relationship. However, they cannot target a chosen pocket in a protein. To address this, a pocket centric virtual ligand screening approach is required. Here, we employ a new, iterative implementation of a pocket and ligand-similarity based approach to virtual ligand screening to predict small molecule binders for the olfactomedin domain of human myocilin implicated in glaucoma. Small-molecule binders of the protein might prevent the aggregation of the protein, commonly seen during glaucoma. First round experimental assessment of the predictions using differential scanning fluorimetry with myoc-OLF yielded 7 hits with a success rate of 12.7%; the best hit had an apparent dissociation constant of 99 nM. By matching to the key functional groups of the best ligand that were likely involved in binding, the affinity of the best hit was improved by almost 10,000 fold from the high nanomolar to the low picomolar range. Thus, this study provides preliminary validation of the methodology on a medically important glaucoma associated protein.