AI Insight
This study identifies TMEM63B, previously known as a mechanosensitive channel, as a contributor to noxious heat sensation in dorsal root ganglion neurons. Researchers found that mice lacking TMEM63B showed reduced heat sensitivity, with neurons exhibiting diminished calcium responses and elevated temperature thresholds for activation. The heat-sensing function of TMEM63B was significantly enhanced by arachidonic acid, indicating that membrane lipid composition modulates its thermosensitive properties.
Why it matters
These findings reveal a new molecular pathway for heat pain detection beyond the well-known TRP channels, potentially opening avenues for developing novel pain management therapies targeting TMEM63B. Understanding lipid-dependent modulation of this channel could lead to more sophisticated approaches for treating chronic pain conditions involving abnormal heat sensitivity.
Understand the Science
by Chang Ye, Yan-Yu Zang, Gui-Fang Duan, Jiang Chen, Dan Wu, Dan Wang, Changlin Li, Yun Xu, Tianjiao Xia, Xiaoping Gu, Yun Stone Shi
In mammals, heat sensation is primarily mediated by thermosensitive channels, particularly transient receptor potential (TRP) channels, in dorsal root ganglion (DRG) neurons. However, whether additional channels contribute to noxious heat detection remains unclear. Here, we investigated the role of the mechanosensitive cation channel TMEM63B in DRG neurons and unexpectedly discovered its involvement in noxious thermosensation rather than mechanosensation. TMEM63B was broadly expressed in DRG neurons, and its global knockout or DRG-specific conditional knockout markedly reduced heat sensitivity. Deletion of TMEM63B significantly attenuated heat-induced calcium responses and currents in DRG neurons and elevated the temperature threshold for action potential initiation. Recombinant TMEM63B exhibited moderate heat response in calcium imaging assays. Notably, in the presence of arachidonic acid, TMEM63B was strongly activated by heat, suggesting that its thermosensitivity is modulated by the membrane lipid environment. Together, these findings identify TMEM63B as a novel channel contributing to heat sensation and reveal a lipid-dependent modulation of its channel activity.