Calcium homeostasis modulator protein 5 (CALHM5)

Calcium homeostasis modulator protein 5 (CALHM5) is a large pore channel protein that assembles as an undecamer in the plasma membrane with four transmembrane helices and an unusually large hydrophobic pore stabilized by tightly bound membrane lipids[1][2][3][4]. It is predicted to participate in monoatomic cation transmembrane transport and ATP export[5]. CALHM5 shares key structural features with other CALHM family members but displays unique pore architecture and gating mechanisms involving lipid interactions. While its precise physiological role remains under study, dysfunction in related CALHM channels is implicated in neuronal pathology and neurodegenerative diseases such as Alzheimer’s disease[4]. The identification of its channel structure offers foundational insight for future functional studies and potential therapeutic targeting. No specific drugs or small molecules targeting CALHM5 are currently known.

Other names

CALHM5C6orf188FAM26EdJ493F7.3MGC45451family with sequence similarity 26 member Eprotein FAM26E

Lipid-mediated gating (lipid binding within the channel pore stabilizes and regulates open/closed states) Putative modulation of ATP and ion transport (largely inferred from CALHM family properties)