title: Novel transcripts in the maxillary venom glands of advanced snakes.
abstract: Venom proteins are added to reptile venoms through duplication of a body protein gene, with the duplicate tissue-specifically expressed in the venom gland. Molecular scaffolds are recruited from a wide range of tissues and with a similar level of diversity of ancestral activity. Transcriptome studies have proven an effective and efficient tool for the discovery of novel toxin scaffolds. In this study, we applied venom gland transcriptomics to a wide taxonomical diversity of advanced snakes and recovered transcripts encoding three novel protein scaffold types lacking sequence homology to any previously characterised snake toxin type: lipocalin, phospholipase A2 (type IIE) and vitelline membrane outer layer protein. In addition, the first snake maxillary venom gland isoforms were sequenced of ribonuclease, which was only recently sequenced from lizard mandibular venom glands. Further, novel isoforms were also recovered for the only recently characterised veficolin toxin class also shared between lizard and snake venoms. The additional complexity of snake venoms has important implications not only for understanding their molecular evolution, but also reinforces the tremendous importance of venoms as a diverse bio-resource.
authors.affiliation: Venom Evolution Laboratory, School of Biological Sciences, University of Queensland, St Lucia, Queensland 4072, Australia. bgfry@uq.edu.au
authors.forename: Bryan G
authors.initials: BG
authors.lastname: Fry
authors.forename: Holger
authors.initials: H
authors.lastname: Scheib
authors.forename: Inacio
authors.initials: I
authors.lastname: de L M Junqueira de Azevedo
authors.forename: Debora Andrade
authors.initials: DA
authors.lastname: Silva
authors.forename: Nicholas R
authors.initials: NR
authors.lastname: Casewell
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D019143:Evolution, Molecular; D015723:Gene Library; D054834:Lipocalins / Q000032:analysis / Q000737:chemistry / Q000235:genetics; D008116:Lizards / Q000378:metabolism; D008969:Molecular Sequence Data; D054467:Phospholipases A2 / Q000032:analysis / Q000737:chemistry / Q000235:genetics; D010802:Phylogeny; D011487:Protein Conformation; D012260:Ribonucleases / Q000378:metabolism; D012469:Salivary Glands / Q000378:metabolism; D012910:Snake Venoms / Q000737:chemistry* / Q000145:classification* / Q000235:genetics*; D012911:Snakes / Q000378:metabolism*; D059467:Transcriptome
chemical_list: D054834:Lipocalins; D012910:Snake Venoms; D012260:Ribonucleases; D054467:Phospholipases A2