Biochemical and Electrophysiological Characterization of Two Sea Anemone Type 1 Potassium Toxins from a Geographically Distant Population of Bunodosoma caissarum

Author(s)

Orts, Diego J. B. ^{[1, 2]} ; Peigneur, Steve ^[3] ; Madio, Bruno ^[1] ; Cassoli, Juliana S. ^[4] ; Montandon, Gabriela G. ^[4] ; Pimenta, Adriano M. C. ^[4] ; Bicudo, Jose E. P. W. ^[1] ; Freitas, Jose C. ^[1] ; Zaharenko, Andre J. ^[5] ; Tytgat, Jan ^[3]

Affiliation

^[1] Univ Sao Paulo, Inst Biosci, Dept Physiol, BR-05508090 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Ctr Marine Biol, BR-11600000 Sao Sebastiao, SP - Brazil

^[3] Univ Leuven KU Leuven, Toxicol Lab, B-3000 Louvain - Belgium

^[4] Univ Fed Minas Gerais, Inst Biol Sci, Lab Venoms & Anim Toxins, BR-31270901 Belo Horizonte, MG - Brazil

^[5] Inst Butantan, Genet Lab, BR-05503900 Sao Paulo - Brazil

• Document type: Journal article
• Source: MARINE DRUGS; v. 11, n. 3, p. 655-679, MAR 2013.
• Web of Science Citations: 17

Abstract

Sea anemone (Cnidaria, Anthozoa) venom is an important source of bioactive compounds used as tools to study the pharmacology and structure-function of voltage-gated K+ channels (K-V). These neurotoxins can be divided into four different types, according to their structure and mode of action. In this work, for the first time, two toxins were purified from the venom of Bunodosoma caissarum population from Saint Peter and Saint Paul Archipelago, Brazil. Sequence alignment and phylogenetic analysis reveals that BcsTx1 and BcsTx2 are the newest members of the sea anemone type 1 potassium channel toxins. Their functional characterization was performed by means of a wide electrophysiological screening on 12 different subtypes of K-V channels (K(V)1.1-K(V)1.6; K(V)2.1; K(V)3.1; K(V)4.2; K(V)4.3; hERG and Shaker IR). BcsTx1 shows a high affinity for rKv1.2 over rKv1.6, hKv1.3, Shaker IR and rKv1.1, while Bcstx2 potently blocked rKv1.6 over hKv1.3, rKv1.1, Shaker IR and rKv1.2. Furthermore, we also report for the first time a venom composition and biological activity comparison between two geographically distant populations of sea anemones. (AU)

• FAPESP's process: 11/21031-6 - Analysis of the mechanism of action involved in the selective activity of Abe III 1.3 in voltage-dependent K+ channels
• Grantee: Diego Jose Orts y Belato
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• FAPESP's process: 09/07128-7 - Sea anemones neurotoxins as tools to study the physiology of voltage-gated potassium channels
• Grantee: Diego Jose Orts y Belato
• Support Opportunities: Scholarships in Brazil - Master