title: Venomics profiling of Thamnodynastes strigatus unveils matrix metalloproteinases and other novel proteins recruited to the toxin arsenal of rear-fanged snakes.
abstract: Rear-fanged and aglyphous snakes are usually considered not dangerous to humans because of their limited capacity of injecting venom. Therefore, only a few studies have been dedicated to characterizing the venom of the largest parcel of snake fauna. Here, we investigated the venom proteome of the rear-fanged snake  Thamnodynastes strigatus , in combination with a transcriptomic evaluation of the venom gland. About 60% of all transcripts code for putative venom components. A striking finding is that the most abundant type of transcript (∼47%) and also the major protein type in the venom correspond to a new kind of matrix metalloproteinase (MMP) that is unrelated to the classical snake venom metalloproteinases found in all snake families. These enzymes were recently suggested as possible venom components, and we show here that they are proteolytically active and probably recruited to venom from a MMP-9 ancestor. Other unusual proteins were suggested to be venom components: a protein related to lactadherin and an EGF repeat-containing transcript. Despite these unusual molecules, seven toxin classes commonly found in typical venomous snakes are also present in the venom. These results support the evidence that the arsenals of these snakes are very diverse and harbor new types of biologically important molecules.
authors.affiliation: Centro de Biotecnologia, Instituto Butantan, Av. Vital Brazil, 1500, São Paulo, SP, 05503-900, Brazil.
authors.forename: Ana T C
authors.initials: AT
authors.lastname: Ching
authors.forename: Adriana F
authors.initials: AF
authors.lastname: Paes Leme
authors.forename: André
authors.initials: A
authors.lastname: Zelanis
authors.forename: Marisa M T
authors.initials: MM
authors.lastname: Rocha
authors.forename: Maria de Fátima D
authors.initials: Mde F
authors.lastname: Furtado
authors.forename: Débora Andrade
authors.initials: DA
authors.lastname: Silva
authors.forename: Monique R O
authors.initials: MR
authors.lastname: Trugilho
authors.forename: Surza L G
authors.initials: SL
authors.lastname: da Rocha
authors.forename: Jonas
authors.initials: J
authors.lastname: Perales
authors.forename: Paulo L
authors.initials: PL
authors.lastname: Ho
authors.forename: Solange M T
authors.initials: SM
authors.lastname: Serrano
authors.forename: Inácio L M
authors.initials: IL
authors.lastname: Junqueira-de-Azevedo
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017812:Colubridae / Q000378:metabolism*; D020782:Matrix Metalloproteinases / Q000737:chemistry* / Q000145:classification; D008969:Molecular Sequence Data; D010802:Phylogeny; D011485:Protein Binding; D020543:Proteome / Q000737:chemistry* / Q000145:classification; D040901:Proteomics / Q000379:methods*; D016415:Sequence Alignment; D012910:Snake Venoms / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000145:classification / Q000378:metabolism; D059467:Transcriptome
chemical_list: D020543:Proteome; D012910:Snake Venoms; D020782:Matrix Metalloproteinases