title: Adaptive radiation of venomous marine snail lineages and the accelerated evolution of venom peptide genes.
abstract: An impressive biodiversity (>10,000 species) of marine snails (suborder Toxoglossa or superfamily Conoidea) have complex venoms, each containing approximately 100 biologically active, disulfide-rich peptides. In the genus Conus, the most intensively investigated toxoglossan lineage (∼500 species), a small set of venom gene superfamilies undergo rapid sequence hyperdiversification within their mature toxin regions. Each major lineage of Toxoglossa has its own distinct set of venom gene superfamilies. Two recently identified venom gene superfamilies are expressed in the large Turridae clade, but not in Conus. Thus, as major venomous molluscan clades expand, a small set of lineage-specific venom gene superfamilies undergo accelerated evolution. The juxtaposition of extremely conserved signal sequences with hypervariable mature peptide regions is unprecedented and raises the possibility that in these gene superfamilies, the signal sequences are conserved as a result of an essential role they play in enabling rapid sequence evolution of the region of the gene that encodes the active toxin.
authors.affiliation: Biology Department, University of Utah, Salt Lake City, Utah, USA. olivera@biology.utah.edu
authors.forename: Baldomero M
authors.initials: BM
authors.lastname: Olivera
authors.forename: Maren
authors.initials: M
authors.lastname: Watkins
authors.forename: Pradip
authors.initials: P
authors.lastname: Bandyopadhyay
authors.forename: Julita S
authors.initials: JS
authors.lastname: Imperial
authors.forename: Edgar P Heimer
authors.initials: EP
authors.lastname: de la Cotera
authors.forename: Manuel B
authors.initials: MB
authors.lastname: Aguilar
authors.forename: Estuardo López
authors.initials: EL
authors.lastname: Vera
authors.forename: Gisela P
authors.initials: GP
authors.lastname: Concepcion
authors.forename: Arturo
authors.initials: A
authors.lastname: Lluisma
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D020916:Conotoxins / Q000235:genetics*; D017124:Conserved Sequence; D052078:Conus Snail / Q000235:genetics*; D019143:Evolution, Molecular; D005787:Gene Frequency; D008957:Models, Genetic; D008969:Molecular Sequence Data; D021382:Protein Sorting Signals / Q000235:genetics; D012641:Selection, Genetic; D017386:Sequence Homology, Amino Acid
chemical_list: D020916:Conotoxins; D021382:Protein Sorting Signals