HINT1

Histidine triad nucleotide-binding protein 1 (HINT1) functions as a zinc- and calmodulin-regulated cysteine SUMO protease that modulates protein sumoylation^[1]. Mechanistically, HINT1 interacts with transcription factors and signaling proteins, including teneurin1, RGSZ2, PKCγ, and Raf-1, influencing neural and tumor-associated pathways^[1][2][3]. In the central nervous system, HINT1 regulates postsynaptic dopamine receptor activity and modulates behavioral responses to psychostimulants, implicating it in schizophrenia-related circuits^[4]. HINT1 also participates in oxidative stress and apoptosis in the prefrontal cortex via the PKCε/ALDH-2/4HNE pathway, supporting its relevance in major depressive disorder models^[5]. Compared with its homolog HINT2, which is liver- and mitochondria-specific, HINT1 exhibits ubiquitous expression and distinct nuclear-cytosolic localization, underscoring isoform-specific functions in neuronal signaling and tumor suppression^[6]. In experimental pharmacology, HINT1 deletion in mice leads to bipolar-like behaviors, providing a model for testing σ1R antagonists and other modulators of glutamatergic neurotransmission^[7]. Furthermore, HINT1 is required for cannabinoid receptor-mediated regulation of NMDA receptor activity, positioning it as a critical mediator in neuroprotective signaling^[2]. Collectively, HINT1 integrates post-translational modification, neurotransmission, and apoptotic pathways, establishing its utility as a target for mechanistic studies and therapeutic exploration^{[1][4][5][2][7][3]}.