Transient Receptor Potential Cation Channel Subfamily P Member 3 (TRPC3)

Transient receptor potential cation channel subfamily C member 3 (TRPC3) is a member of the canonical transient receptor potential (TRPC) subfamily of ion channels, which are nonselective cation channels permeable to calcium, sodium, and potassium. TRPC3 is prominently expressed in the brain, heart, and other tissues, where it plays a key role in calcium homeostasis and cellular signaling[1][2]. Structurally, TRPC3 forms a tetrameric channel with six transmembrane domains (S1–S6), intracellular N- and C-termini, and a pore region formed by the P-loop between S5 and S6[1]. The channel is uniquely sensitive to activation by diacylglycerol (DAG) via the phospholipase C pathway, distinguishing it from other TRPC channels[2]. TRPC3 also contributes to store-operated calcium entry, responding to depletion of endoplasmic reticulum calcium stores[1]. Unusual structural features include a long third transmembrane helix (S3) that extends into the extracellular space, possibly serving as a sensor for external stimuli, and a distinctive cytoplasmic domain organization involving ankyrin repeats and coiled-coil domains that contribute to channel assembly and gating[1]. TRPC3 is implicated in several human diseases, including neurodegenerative disorders, cardiac hypertrophy, spinocerebellar ataxia, hypertension, and memory impairment[1][3]. Its modulation by pharmacological agents such as the agonist GSK-1702934A and the inhibitor Pyr3 highlights its potential as a therapeutic target[3]. However, due to its broad physiological roles and the risk of off-target effects, careful development of selective modulators is essential.

Other names

TRP-3TrpC3Transient receptor protein 3Transient receptor potential channel 3

Activation via diacylglycerol (DAG) following phospholipase C (PLC) pathway stimulation Store-operated calcium entry upon endoplasmic reticulum calcium depletion Modulation by extracellular stimuli (putative sensor function for the extracellular domain) Allosteric regulation by intracellular domains, including coiled-coil and ankyrin repeat domains Inhibition of channel activity by targeted small molecules (e.g., Pyr3)