Calcium homeostasis modulator protein 3 (CALHM3)

Calcium homeostasis modulator protein 3 (CALHM3) is a pore-forming subunit of a voltage-gated ion channel, best known for its essential role in the sensory perception of sweet, bitter, and umami tastes[3][4][5][6]. CALHM3 is co-expressed with CALHM1 in type II taste bud cells, where the two proteins assemble into a hetero-hexameric channel complex that functions as a fast-activating, voltage-gated ATP-release channel[4][6]. This ATP release is critical for activating afferent neural gustatory pathways during taste transduction. CALHM3 alone or with CALHM1 is predicted to mediate monoatomic cation (such as Ca²⁺ and Na⁺) flux across the plasma membrane and is mainly localized to the basolateral plasma membrane of taste cells[2][3][5][6]. While primarily studied in the context of taste, CALHM family channels have also been implicated in neuronal excitability and certain neurological pathologies, though direct evidence for CALHM3’s involvement in diseases (such as Alzheimer's or depression) is sparse, with stronger evidence for family members such as CALHM1[1][6]. No drugs, therapeutic mechanisms, or established biomarker roles are currently reported for CALHM3 specifically.

Other names

Calcium homeostasis modulator 3FAM26AbA225H22.7Protein Afamily with sequence similarity 26, member A