مقالات پذیرفته شده در هفتمین کنگره بین المللی زیست پزشکی
Characterization and structure determination of a potent potassium channel blocker neurotoxin from the venom gland of Mesoburhus eupeus
Characterization and structure determination of a potent potassium channel blocker neurotoxin from the venom gland of Mesoburhus eupeus
Masoumeh Baradaran,1,*
1. Toxicology Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Introduction: Scorpion venom is a great source of potent pharmacologically active agents. Different studies demonstrate the pharmacological effect of venom components for treatment of various diseases, including cancer, microbial, autoimmune and cardiovascular diseases. Moreover, some crucial enzymes such as phospholipase (A, B, C, and D), hyaluronidase, enolase along with toxins affecting ion channels (Na+, K+, Ca2+, Cl-) make an important part of the scorpion venom. Mesobuthus eupeus, a member of Buthidae family, is the most frequent scorpion species living in Iran. It is responsible for many of reported scorpion stings referring to hospitals and health centres. Prescience of some short chain and low molecular weight neurotoxins have been demonstrated in the venom of this scorpion.
Methods: In the present study, we analysed the transcriptome of the venom gland of M. eupeus obtained using total RNA extraction and cDNA library synthesis. The final transcriptome was blasted against peptides and proteins databases, including Uniprot and NCBI, in order to find a potassium channel blocker neurotoxin. Bioinformatics software was applied to analysis the physico-chemical properties of the identified protein. Three-dimensional structure of the protein was achieved by homology modelling. MD simulation was finally run to assess the protein structure.
Results: A potent potassium channel blocker was found in the transcriptome of the venom gland of M. eupes. It was submitted to the Gen Bank under the name of meuK-toxin. It is a water-soluble peptide with molecular weight of, 4271 g/mol and theoretical pI of 4.47. The structure of meuK-toxin consists of a conserved LCN-type cysteine-stabilized alpha/beta domain. This domain is stabilized by six cysteine residues. meuK-toxin is structurally analogous to scorpion toxins specific for apamin-sensitive potassium channel.
Conclusion: Here we found and characterized a small, potent potassium channel blocker derived from a scorpion venom gland. This gives us a basis information keys to investigate the function of this protein in future to define underlying physiological processes or maybe design new selective useful drug.