001037779 001__ 1037779 001037779 005__ 20250203124519.0 001037779 0247_ $$2doi$$a10.1073/pnas.2409097121 001037779 0247_ $$2ISSN$$a0027-8424 001037779 0247_ $$2ISSN$$a1091-6490 001037779 0247_ $$2datacite_doi$$a10.34734/FZJ-2025-00931 001037779 0247_ $$2pmid$$a39365813 001037779 0247_ $$2WOS$$aWOS:001352155400008 001037779 037__ $$aFZJ-2025-00931 001037779 082__ $$a500 001037779 1001_ $$00000-0001-5868-1003$$aOrtega-Ramírez, Audrey Magdalena$$b0 001037779 245__ $$aA conserved peptide-binding pocket in HyNaC/ASIC ion channels 001037779 260__ $$aWashington, DC$$bNational Acad. of Sciences$$c2024 001037779 3367_ $$2DRIVER$$aarticle 001037779 3367_ $$2DataCite$$aOutput Types/Journal article 001037779 3367_ $$0PUB:(DE-HGF)16$$2PUB:(DE-HGF)$$aJournal Article$$bjournal$$mjournal$$s1737998579_9344 001037779 3367_ $$2BibTeX$$aARTICLE 001037779 3367_ $$2ORCID$$aJOURNAL_ARTICLE 001037779 3367_ $$00$$2EndNote$$aJournal Article 001037779 520__ $$aThe only known peptide-gated ion channels—FaNaCs/WaNaCs and HyNaCs—belong to different clades of the DEG/ENaC family. FaNaCs are activated by the short neuropeptide FMRFamide, and HyNaCs by Hydra RFamides, which are not evolutionarily related to FMRFamide. The FMRFamide-binding site in FaNaCs was recently identified in a cleft atop the large extracellular domain. However, this cleft is not conserved in HyNaCs. Here, we combined molecular modeling and site-directed mutagenesis and identified a putative binding pocket for Hydra-RFamides in the extracellular domain of the heterotrimeric HyNaC2/3/5. This pocket localizes to only one of the three subunit interfaces, indicating that this trimeric ion channel binds a single peptide ligand. We engineered an unnatural amino acid at the putative binding pocket entrance, which allowed covalent tethering of Hydra RFamide to the channel, thereby trapping the channel in an open conformation. The identified pocket localizes to the same region as the acidic pocket of acid-sensing ion channels (ASICs), which binds peptide ligands. The pocket in HyNaCs is less acidic, and both electrostatic and hydrophobic interactions contribute to peptide binding. Collectively, our results reveal a conserved ligand-binding pocket in HyNaCs and ASICs and indicate independent evolution of peptide-binding cavities in the two subgroups of peptide-gated ion channels. 001037779 536__ $$0G:(DE-HGF)POF4-5252$$a5252 - Brain Dysfunction and Plasticity (POF4-525)$$cPOF4-525$$fPOF IV$$x0 001037779 588__ $$aDataset connected to CrossRef, Journals: juser.fz-juelich.de 001037779 7001_ $$0P:(DE-Juel1)181061$$aAlbani, Simone$$b1 001037779 7001_ $$0P:(DE-HGF)0$$aBachmann, Michèle$$b2 001037779 7001_ $$0P:(DE-HGF)0$$aSchmidt, Axel$$b3 001037779 7001_ $$0P:(DE-HGF)0$$aPinoé-Schmidt, Manuela$$b4 001037779 7001_ $$0P:(DE-HGF)0$$aAssmann, Marc$$b5 001037779 7001_ $$0P:(DE-HGF)0$$aAugustinowski, Katrin$$b6 001037779 7001_ $$0P:(DE-Juel1)145921$$aRossetti, Giulia$$b7 001037779 7001_ $$00000-0002-7635-9883$$aGründer, Stefan$$b8$$eCorresponding author 001037779 773__ $$0PERI:(DE-600)1461794-8$$a10.1073/pnas.2409097121$$gVol. 121, no. 41, p. e2409097121$$n41$$pe2409097121$$tProceedings of the National Academy of Sciences of the United States of America$$v121$$x0027-8424$$y2024 001037779 8564_ $$uhttps://juser.fz-juelich.de/record/1037779/files/Author%20version.pdf$$yOpenAccess 001037779 8564_ $$uhttps://juser.fz-juelich.de/record/1037779/files/ortega-ram%C3%ADrez-et-al-2024-a-conserved-peptide-binding-pocket-in-hynac-asic-ion-channels.pdf$$yOpenAccess 001037779 909CO $$ooai:juser.fz-juelich.de:1037779$$pdnbdelivery$$pdriver$$pVDB$$popen_access$$popenaire 001037779 9101_ $$0I:(DE-588b)5008462-8$$6P:(DE-Juel1)181061$$aForschungszentrum Jülich$$b1$$kFZJ 001037779 9101_ $$0I:(DE-588b)5008462-8$$6P:(DE-Juel1)145921$$aForschungszentrum Jülich$$b7$$kFZJ 001037779 9131_ $$0G:(DE-HGF)POF4-525$$1G:(DE-HGF)POF4-520$$2G:(DE-HGF)POF4-500$$3G:(DE-HGF)POF4$$4G:(DE-HGF)POF$$9G:(DE-HGF)POF4-5252$$aDE-HGF$$bKey Technologies$$lNatural, Artificial and Cognitive Information Processing$$vDecoding Brain Organization and Dysfunction$$x0 001037779 9141_ $$y2024 001037779 915__ $$0StatID:(DE-HGF)0200$$2StatID$$aDBCoverage$$bSCOPUS$$d2024-12-10 001037779 915__ $$0StatID:(DE-HGF)0160$$2StatID$$aDBCoverage$$bEssential Science Indicators$$d2024-12-10 001037779 915__ $$0StatID:(DE-HGF)1050$$2StatID$$aDBCoverage$$bBIOSIS Previews$$d2024-12-10 001037779 915__ $$0StatID:(DE-HGF)1190$$2StatID$$aDBCoverage$$bBiological Abstracts$$d2024-12-10 001037779 915__ $$0StatID:(DE-HGF)0600$$2StatID$$aDBCoverage$$bEbsco Academic Search$$d2024-12-10 001037779 915__ $$0StatID:(DE-HGF)1040$$2StatID$$aDBCoverage$$bZoological Record$$d2024-12-10 001037779 915__ $$0StatID:(DE-HGF)0100$$2StatID$$aJCR$$bP NATL ACAD SCI USA : 2022$$d2024-12-10 001037779 915__ $$0LIC:(DE-HGF)CCBYNCND4$$2HGFVOC$$aCreative Commons Attribution-NonCommercial-NoDerivs CC BY-NC-ND 4.0 001037779 915__ $$0StatID:(DE-HGF)9910$$2StatID$$aIF >= 10$$bP NATL ACAD SCI USA : 2022$$d2024-12-10 001037779 915__ $$0StatID:(DE-HGF)1030$$2StatID$$aDBCoverage$$bCurrent Contents - Life Sciences$$d2024-12-10 001037779 915__ $$0StatID:(DE-HGF)0113$$2StatID$$aWoS$$bScience Citation Index Expanded$$d2024-12-10 001037779 915__ $$0StatID:(DE-HGF)0150$$2StatID$$aDBCoverage$$bWeb of Science Core Collection$$d2024-12-10 001037779 915__ $$0StatID:(DE-HGF)0510$$2StatID$$aOpenAccess 001037779 915__ $$0StatID:(DE-HGF)0030$$2StatID$$aPeer Review$$bASC$$d2024-12-10 001037779 915__ $$0StatID:(DE-HGF)1060$$2StatID$$aDBCoverage$$bCurrent Contents - Agriculture, Biology and Environmental Sciences$$d2024-12-10 001037779 915__ $$0StatID:(DE-HGF)0430$$2StatID$$aNational-Konsortium$$d2024-12-10$$wger 001037779 915__ $$0StatID:(DE-HGF)0300$$2StatID$$aDBCoverage$$bMedline$$d2024-12-10 001037779 915__ $$0StatID:(DE-HGF)0199$$2StatID$$aDBCoverage$$bClarivate Analytics Master Journal List$$d2024-12-10 001037779 920__ $$lyes 001037779 9201_ $$0I:(DE-Juel1)INM-9-20140121$$kINM-9$$lComputational Biomedicine$$x0 001037779 9201_ $$0I:(DE-Juel1)IAS-5-20120330$$kIAS-5$$lComputational Biomedicine$$x1 001037779 980__ $$ajournal 001037779 980__ $$aVDB 001037779 980__ $$aUNRESTRICTED 001037779 980__ $$aI:(DE-Juel1)INM-9-20140121 001037779 980__ $$aI:(DE-Juel1)IAS-5-20120330 001037779 9801_ $$aFullTexts