Characterization of the electrosensory receptor in axolotl and the role of voltage-gatedpotassium channels in electrosensitivity.

The electrosensory system is an important component of the lateral line system in certain aquatic vertebrates. Ampullary organs (AOs), a type of highly sensitive electroreceptor, can detect weak, low-frequency electric fields, playing a critical role in prey detection and predator avoidance in certain species. However, the molecular mechanisms underlying AO function remain poorly understood. The axolotl (Ambystoma mexicanum), a model organism in developmental biology, also possesses AOs. Studies on its AOs are primarily confined to developmental origin and early-stages morphology, with limited attention to molecular and functional properties. In this study, we investigated the distribution, morphological, and transcriptome of juvenile axolotl AOs. In vivo and section staining results affirmed that juvenile axolotl AOs were located exclusively in the head, with a typical canal formed by epidermal invagination. Multiple conservatively expressed lateral line receptor marker genes are likely to be expressed in the AOs of the axolotl. We further found that genes encoding voltage-gated potassium channels (Kv) were highly expressed in AOs, and pharmacological inhibition of these channels impaired electrosensory behavior in axolotls, supporting an important role for Kv channels in axolotl electrosensitivity. Together, these findings enrich our understanding of AO morphology and function, and provide an important foundation for uncovering the molecular mechanisms underlying AO function.