TRPM5 Gene: Function, Expression, and Disease Associations | Biomedical SEO

The TRPM5 gene encodes a calcium-activated, non-selective cation channel that is a member of the transient receptor potential (TRP) channel family. TRPM5 is primarily involved in taste transduction, particularly in sweet, bitter, and umami taste signaling, where it mediates depolarization of taste receptor cells in response to G-protein-coupled receptor activation. It is also expressed in other tissues, including the pancreas, intestine, and brain, where it contributes to insulin secretion, gut hormone release, and neuronal excitability. TRPM5 channels are characterized by their activation by intracellular calcium and their permeability to monovalent cations such as sodium and potassium, with a relatively low calcium permeability. The channel plays a critical role in cellular signaling pathways and has been implicated in various physiological and pathological processes.

Tissue Expression

Cell Line Expression

Hotspot Mutations

Mutation functional classification

• Taste transduction (KEGG: hsa04742)

• Calcium signaling pathway (KEGG: hsa04020)

• GPCR downstream signaling (e.g.

• PLC-beta pathway)

• Insulin secretion pathway (KEGG: hsa04911)

TRPM5 is a 1,165-amino acid protein with six transmembrane domains, forming a tetrameric cation channel. It is activated by intracellular calcium (Ca2+) in a calmodulin-dependent manner, and it conducts monovalent cations (Na+, K+, Cs+) with minimal Ca2+ permeability. The channel is voltage-sensitive and exhibits outward rectification. TRPM5 is critical for depolarizing taste receptor cells upon taste stimuli, leading to ATP release and neurotransmission. In pancreatic beta cells, TRPM5 amplifies glucose-induced depolarization, facilitating insulin exocytosis. The protein is also involved in gut hormone secretion and neuronal signaling. Post-translational modifications include phosphorylation and glycosylation, which modulate channel activity.