Venoms from different snake families may have many deadly ingredients in common, according to a new study1. Researchers have discovered three-finger toxins (a family of poisons earlier thought to occur only in the family Elapidae) in a subspecies of the Massasauga Rattlesnake.
The researchers used venom glands from a rare rattlesnake that lives in arid and desert grasslands – the Desert Massasauga (Sistrurus catenatus edwardsii). They constructed a cDNA library of the snake's venom gland and created 576 tagged sequences. Alongside a wide range of known venom toxin sequences, they also found three-finger toxin-like transcripts. The team also spotted a novel toxin-like transcript generated by the fusion of two individual toxin genes, a mechanism not previously observed in toxin evolution.
Earlier research has identified venom compounds using protein chemistry or individual gene cloning methods. In this, less abundant toxins often went untraced. The library method has now revealed new toxin genes and families of toxins. A diversity of toxins will provide a huge range of bioactive polypeptides, which could help make new therapeutic agents.
The authors of this work are from: Center for Post Graduate Studies, Sri Bhagawan Mahaveer Jain College, Bangalore, India; School of Biological Sciences, University of Northern Colorado, US; Protein Science Laboratory, Department of Biological Sciences, National University of Singapore, Singapore; Department of Biochemistry, Virginia Commonwealth, University Medical College of Virginia, Richmond, US.
