Transmembrane protein 150C (TMEM150C) also known as Tentonin-3 (TTN3), is a small protein composed of 249 amino acids comprising six transmembrane domains.

TMEM150C which was first thought to be a mechanosensitive ion channel that confers a relatively slow inactivating current in proprioceptive neurons in mouse dorsal root ganglion (DRG)1. Later studies, however, showed that the mechanosensitive currents attributed to TMEM150C in different cell setups, could be attributed to the presence of endogenous Piezo1 channels².

Although, some controversy still remains, it is generally accepted that TMEM150C does not form a mechanosensitive channel per se, but rather it functions as a general regulator or sensor, of mechanosensitive channels like Piezo1, Piezo2 and TREK1 (K2P2.1) ^2,3.

TMEM150C has also been described in the aortic arch and nodose ganglia neurons, where it is involved in the mechanotransduction of arterial pressure to electrical signals in baroreceptors. Dysregulation of TMEM150C alters the sensitivity of the baroreflex, a cardiovascular reflex that is essential for blood pressure homeostasis, leading to diseases such as hypertension, stroke, and heart failure ⁴.

Furthermore, recent evidence suggests that TMEM150C functions as a stretch-activated cation channel in pancreatic β cells, contributing to insulin secretion induced by high glucose levels and hypotonicity. Whether TMEM150C functions in this context as a stretch activated channel itself or whether it functions in conjunction with other proposed stretch-activated channels like TRPV4 or TRPV2, remains to be seen ^3,5.