Molecular evolution, functional variation, and proposed nomenclature of the gene family that includes sphingomyelinase D in sicariid spider venoms.

ABSTRACT: The venom enzyme sphingomyelinase D (SMase D) in the spider family Sicariidae (brown or fiddleback spiders [Loxosceles] and six-eyed sand spiders [Sicarius]) causes dermonecrosis in mammals. SMase D is in a gene family with multiple venom-expressed members that vary in functional specificity. We analyze molecular evolution of this family and variation in SMase D activity among crude venoms using a data set that represents the phylogenetic breadth of Loxosceles and Sicarius. We isolated a total of 190 nonredundant nucleotide sequences encoding 168 nonredundant amino acid sequences of SMase D homologs from 21 species. Bayesian phylogenies support two major clades that we name alpha and beta, within which we define seven and three subclades, respectively. Sequences in the alpha clade are excl

SUBMITTER: Binford GJ 

PROVIDER: S-EPMC2767091 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature