New Publication: Hybridisation in the Tarantula Hobby

Posted by
  New Publication: Hybridisation in the Tarantula Hobby I am pleased to share the publication of my latest paper, “Hybridisation in the Tarantula Hobby: Ethical Boundaries and Biological Consequences,” in the Journal of the British Tarantula Society , Volume 41, No. 1, September 2026. The paper addresses an issue that deserves serious consideration within the tarantula community: hybridisation and its potential long-term effects on the integrity of captive lineages. More Than a Breeding Decision The tarantula hobby has changed considerably over the past several decades. What was once a relatively small community has grown into an international network of keepers, breeders, vendors, researchers, and societies. Captive breeding has contributed enormously to that growth, improving husbandry knowledge and increasing the availability of captive-bred animals. With that success comes responsibility for the lineages we maintain. Hybridisation may seem like an isolated breeding experiment,...

Structural basis of inhibition of human NaV1.8 by the tarantula venom peptide Protoxin-I

Posted by

 


Structural basis of inhibition of human NaV1.8 by the tarantula venom peptide Protoxin-I

Abstract

Voltage-gated sodium channels (NaVs) selectively permit diffusion of sodium ions across the cell membrane and, in excitable cells, are responsible for propagating action potentials. One of the nine human NaV isoforms, NaV1.8, is a promising target for analgesics, and selective inhibitors are of interest as therapeutics. One such inhibitor, the gating-modifier peptide Protoxin-I derived from tarantula venom, blocks channel opening by shifting the activation voltage threshold to more depolarised potentials, but the structural basis for this inhibition has not previously been determined. Using monolayer graphene grids, we report the cryogenic electron microscopy structures of full-length human apo-NaV1.8 and the Protoxin-I-bound complex at 3.1 Angstrom and 2.8 Angstrom resolution, respectively. The apo structure shows an unexpected movement of the Domain I S4-S5 helix, and VSDI was unresolvable. We find that Protoxin-I binds to and displaces the VSDII S3-S4 linker, hindering translocation of the S4II helix during activation.

Structural basis of inhibition of human NaV1.8 by the tarantula venom peptide Protoxin-I
Bryan Neumann, Stephen McCarthy, Shane Gonen, bioRxiv 2024.08.27.609828;