In Memoriam: Giraldo Alayón García

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  In Memoriam: Giraldo Alayón García -  Photo © Facebook/National Museum of Natural History of Cuba In Memoriam: Giraldo Alayón García The arachnological community mourns the loss of Giraldo Alayón García, a Cuban zoologist whose work helped bring the spiders of Cuba and the wider Caribbean into clearer scientific view. As a researcher and curator at Cuba’s National Museum of Natural History, Dr. Alayón devoted decades to studying arachnids. His publications on spider taxonomy, evolution, and biogeography gave other researchers a stronger foundation for understanding the region’s biodiversity. He also shared that knowledge through teaching and scientific exchange far beyond Cuba. For those of us who care about taxonomy, his legacy is a reminder of the patient work behind every species description: examining specimens, recording differences, and preserving knowledge that others can build upon. His contributions will continue to guide the study of Caribbean spiders for years to ...

Singapore blue (Omothymus violaceopes, Abraham, 1924) arboreal tarantula peptide Lv1a preferentially targets NaV1.6 with new world–like pharmacological mechanism

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Singapore blue (Omothymus violaceopes, Abraham, 1924) arboreal tarantula peptide Lv1a preferentially targets NaV1.6 with new world–like pharmacological mechanism

Abstract

Spider venom peptides evolved into bioactive entities modulating ion channels with exceptional selectivity and potency. Unlike New World tarantulas, Old World tarantulas of the family Theraphosidae from Asia, Africa and Oceania lack urticating hair and use envenomation as their primary strategy for predation and defence. In this work, we characterized the venom of the arboreal Asian tarantula Lampropelma violaceopes, also known as Singapore blue, which is endemic to Malaysia and Singapore. L. violaceopes venom contained potent voltage-gated sodium channels (NaV) inhibitors with masses ranging from 3710 to 3942 Da, including Lv1a, a 35 residues peptide with a typical inhibitory cysteine knot motif. Pharmacological profiling of Lv1a revealed a preference for inhibiting human NaV1.6 subtype, whose dysfunction can lead to neurotransmission block, muscle paralysis and potential death. Molecular docking simulations revealed binding of Lv1a to NaV channels occurs in segments 1 and 2 and segments 3 and 4 loops of domain II through electrostatic and hydrophobic interactions governed by residues in loops 1 and 4, and the C-terminal of Lv1a. Although taxa separation occurred, leading to fast-acting Old World tarantulas and New World tarantulas comprising urticating hairs, both utilize the same pharmacophore to modulate NaV channels. This suggests such venom peptides evolved before clades separated and were maintained as tarantulas established worldwide. This work contributes to the understanding of the evolution and structure–function relationship properties of tarantula venom peptides, and is a guide for the development of neuroactive peptides targeting neuronal sodium channel subtypes in concert of sensory and motor pathways.
Cardoso, F. C., Muller, J. A., & Lewis, R. J. (2026). Singapore blue arboreal tarantula peptide Lv1a preferentially targets NaV1.6 with new world–like pharmacological mechanism. Biochemical Pharmacology, 244, 117565. https://doi.org/10.1016/j.bcp.2025.117565