Molecular cloning and nucleotide sequence analysis of encoded anti-insect toxin BotIT2 from the scorpion Buthus occitanus tunetanus venom

• Published in: Archives de l'Institut Pasteur de Tunis Vol. 80; no. 1-4; p. 35
• Main Authors: Bel Haj Rhouma, R, Dkhil, H, Benkhadir, K, Borchani, L, El Ayeb, M, Karoui, H
• Format: Journal Article
• Language: English
• Published: Tunisia 2003
• Subjects: Amino Acid Sequence; Amino Acid Substitution - genetics; Animals; Base Sequence - genetics; Blotting, Western; Cloning, Molecular - methods; DNA, Complementary - genetics; Electrophoresis, Agar Gel; Electrophoresis, Polyacrylamide Gel; Gene Expression - genetics; Insecta - drug effects; Molecular Sequence Data; Neurotoxins - adverse effects; Neurotoxins - chemistry; Random Amplified Polymorphic DNA Technique; Recombinant Fusion Proteins - chemistry; Recombinant Fusion Proteins - genetics; Scorpion Venoms - adverse effects; Scorpion Venoms - chemistry; Scorpion Venoms - classification; Scorpion Venoms - genetics; Scorpion Venoms - isolation & purification; Scorpions; Sodium Channels - drug effects; Structure-Activity Relationship; Tunisia
• ISSN: 0020-2509

Numerous toxins from scorpion venoms are much more toxic to insects than to other animal classes, and possess high affinity to Na+ channels. Many of them active on insects were purified from the venom of Buthus occitanus tunetanus. Using amino acid sequences of BotIT2 and RACE-PCR amplification (Rapid amplification of cDNA ends) technique, we isolated, identified and sequenced the nucleotide sequence from the venom glands of the scorpion Buthus occitanus tunetanus. The cDNA encodes a precursor of an insect toxin of 60 amino acid residues. The deduced nucleotide sequence toxin was identical to the determined amino acid sequence of BotIT2. BotIT2 is more similar to the excitatory toxins in its mode of action and to the depressant toxins in its primary structure.