| First Author | Wu Y | Year | 2025 |
| Journal | Nat Commun | Volume | 16 |
| Issue | 1 | Pages | 2102 |
| PubMed ID | 40025061 | Mgi Jnum | J:364182 |
| Mgi Id | MGI:7868950 | Doi | 10.1038/s41467-025-57358-9 |
| Citation | Wu Y, et al. (2025) HCN4 channels sense temperature and determine heart rate responses to heat. Nat Commun 16(1):2102 |
| abstractText | The hyperpolarization-activated cyclic nucleotide-gated ion channel 4 (HCN4) current increases due to cAMP binding and is well-recognized to contribute to adrenergically driven heart rate acceleration. HCN4 current also increases with heat by an unknown mechanism(s). We use thermodynamical and homology computational modeling, site-directed mutagenesis, and mouse models to identify a concise motif on the S4-S5 linker of HCN4 channels (M407/Y409) that determines HCN4 current (I(f)) responses to heat. This motif is required for heat-triggered rate acceleration in cardiac pacemaker cells, isolated hearts and in vivo. Surprisingly, a loss of function M407/Y409 motif mutation prevented not only normal heat but also cAMP responses, suggesting that the heat-sensing machinery within the S4-S5 linker is essential for operating the cAMP allosteric pathway and is central to HCN4 gating modulation. The M407/Y409 motif is conserved across all HCN family members suggesting that HCN channels participate broadly in coupling heat to changes in cell membrane excitability. |