Cystine knot toxins (CKTs) in spider venoms represent a rich source of novel ligands for varied ion channels. Here, we identified 95 novel putative CKT precursors by analyzing expressed sequence tags of the tarantula Chilobrachys jingzhao venom gland. Phylogenetics analyses revealed one orphan family and six families with sequence similarity to known toxins. To further investigate the relationships of their structures, functions and evolution, we assayed 10 representative toxins for their effect on ion channels, and performed structure model comparisons, evolution analysis and toxin distribution analysis. This study revealed two major types of CKTs: pore-blocking toxins and gating modifier toxins. A few blockers were observed with relatively high abundance and wide distribution, which may be a category of original toxins that block channels conserved in various preys with relatively high specificity. The gating modifier families contain advanced toxins, usually have many members and interact with diverse regulatory components of channels.

We introduce a class of complex-valued biharmonic mappings, denoted by BH 0 φ k ; σ, a, b , together with its subclass TBH 0 φ k ; σ, a, b , and then generalize the discussions in Ali et al. 2010 to the setting of BH 0 φ k ; σ, a, b and TBH 0 φ k ; σ, a, b in a unified way.

We give coefficient estimates for a class of close-to-convex harmonic mappings F , and discuss the Fekete-Szegő problem of it. We also determine a disk |z| < r in which the partial sum s m,n ( f ) is close-to-convex for each f ∈ F . Then, we introduce two classes of polyharmonic mappings HS p and HC p , consider the starlikeness and convexity of them and obtain coefficient estimates for them. Finally, we give a necessary condition for a mapping F to be in the class HC p .