Neuronal subtype-specific expression of γ-enolaseHorvat, Selena (Avtor) Pečar Fonović, Urša (Avtor) Zidar, Nace (Avtor) Doljak, Bojan (Avtor) Kos, Janko (Avtor) Pišlar, Anja (Avtor) cathepsin x regulationenolase isoformsneuronal specific subtypeneurotrophic activityγ-enolaseNeuronal differentiation into specific subtypes is crucial for nervous system development and function, guided by neurotrophic factors. γ-Enolase, a neuron-specific glycolytic enzyme, exhibits neurotrophic-like properties and supports neuronal differentiation; however, its role in specific neuronal subtypes remains unknown. Here, we investigate the role of γ-enolase in differentiation dopaminergic-, cholinergic-, and adrenergic-like neuronal cells. Our results demonstrate that γ-enolase expression is significantly upregulated in differentiated cells, with the highest expression observed in cholinergic-like neurons. Full-length γ-enolase, compared to its truncated form, promoted enhanced neurite outgrowth and increased β-tubulin, a cytoskeletal marker. Conversely, silencing endogenous γ-enolase significantly reduced neurite length, confirming its essential role in driving neuronal morphological maturation. Furthermore, a γ-enolase-derived peptide corresponding to the active C-terminus of γ-enolase significantly promoted neurite outgrowth and increased β-tubulin expression, particularly in cholinergic-like neuronal cells. Notably, γ-enolase activity is regulated by cathepsin X, a lysosomal peptidase that cleaves γ-enolase at its C-terminus, reducing its neurotrophic effects. Confocal microscopy revealed increased co-localization of γ-enolase and cathepsin X in differentiated neuronal cells, emphasizing their interaction in cholinergic-like neurons. Inhibiting cathepsin X preserved active γ-enolase, promoted neuronal differentiation, and altered cytoskeletal marker expression. These findings suggest an important role for γ-enolase in cholinergic-like neuronal cells and propose cathepsin X as a regulatory modulator of γ-enolase activity, suggesting novel therapeutic strategies for neuroregeneration.20262026-03-23 14:59:21Članek v reviji181041UDK: 577.152.34ISSN pri članku: 1559-1174DOI: 10.1007/s12017-025-08902-9COBISS_ID: 272309507sl