New synonymy and combinations in Megamyrmaekion Reuss, 1834 (Araneae: Gnaphosidae)

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  New synonymy and combinations in Megamyrmaekion Reuss, 1834 (Araneae: Gnaphosidae) Abstract The drassodine ground spider genus Megamyrmaekion Reuss, 1834 is recorded from Vietnam for the first time as a result of the following new combinations here proposed: M. luridum (O. Pickard-Cambridge, 1874) comb. nov., ex Drassodes Westring, 1851, and M. vickyae (Sherwood, Marusik, Sharp & Ashmole, 2023) comb. nov., ex Australoechemus Schmidt & Piepho, 1994. Detailed redescriptions and illustrations of the male and female of M. luridum comb. nov., from Vietnam are provided. Additionally, A. celer Schmidt & Piepho, 1994 syn. nov., is recognized as a junior synonym of M. caudatum Reuss, 1834. Drassus tarrhunensis Karsch, 1881 is removed from the synonymy of M. caudatum and provisionally transferred to the genus Megamyrmaekion as M. tarrhunense (Karsch, 1881) comb. nov. Truong, B.P., Le, T.T.S., Uyen, P.T.T., Phan, Q.T. & Hoang, Q.D. (2026) New synonymy and combinations in Meg...

Design of antinociceptive peptide by grafting domains between scorpion β-neurotoxins

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Design of antinociceptive peptide by grafting domains between scorpion β-neurotoxins

Abstract

Neurotoxic peptides from venomous animals have been pointed out as antinociceptive therapeutic leads. Venom peptides have modulation properties on isoforms of voltage-gated sodium channels (VGSC), associated with pathologies such as neuropathic or inflammatory pain. The β-neurotoxins obtained from scorpion venoms are peptides that can alter the kinetics of VGSC by binding to its receptor site 4. CeII8 is a non-lethal scorpion β-neurotoxin that has been reported to interact with hNaV1.7, a VGSC isoform related to the codification and processing of painful stimulus (nociception), and it is involved in pain pathologies. On the other hand, CssII is a lethal scorpion β-neurotoxin that binds mainly to site 4 of hNav1.6. Because of this, we used computational methods and the amino acid sequence of the novo recombinant neurotoxin rCssII-RCR to graft in some of its domains existing amino acids from the non-lethal CeII8 to generate a chimeric peptide with antinociceptive activity, named rCssII-Del-D23A-TCD. This peptide variant was found to have antinociceptive activity in inflammatory and neuropathic pain models with an effect comparable to the mu-opioid receptor agonists DAMGO (H-Tyr-D-Ala-Gly-N(Me) Phe-Gly-ol).
Montero-Dominguez, P. A., Restano-Cassulini, R., Magaña-Ávila, L. C., Almanza, A., Mercado, F., & Corzo, G. (2025). Design of antinociceptive peptide by grafting domains between scorpion β-neurotoxins. Bioorganic Chemistry, 162, 108592. https://doi.org/10.1016/j.bioorg.2025.108592