Phospho‐regulation, nucleotide binding and ion access control in potassium‐chloride cotransporters
Potassium‐coupled chloride transporters (KCCs) play crucial roles in regulating cell volume and intracellular chloride concentration. They are characteristically inhibited under isotonic conditions via phospho‐regulatory sites located within the cytoplasmic termini. Decreased inhibitory phosphorylat...
| Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , , , |
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| Format: | Journal article |
| Language: | English |
| Published: |
EMBO Press
2021
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| _version_ | 1826314882138505216 |
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| author | Chi, G Ebenhoch, R Man, H Tang, H Tremblay, LE Reggiano, G Qiu, X Bohstedt, T Liko, I Almeida, FG Garneau, AP Wang, D McKinley, G Moreau, CP Bountra, KD Abrusci, P Mukhopadhyay, SMM Fernandez‐Cid, A Slimani, S Lavoie, JL Burgess‐Brown, NA Tehan, B DiMaio, F Jazayeri, A Robinson, CV Dürr, KL |
| author_facet | Chi, G Ebenhoch, R Man, H Tang, H Tremblay, LE Reggiano, G Qiu, X Bohstedt, T Liko, I Almeida, FG Garneau, AP Wang, D McKinley, G Moreau, CP Bountra, KD Abrusci, P Mukhopadhyay, SMM Fernandez‐Cid, A Slimani, S Lavoie, JL Burgess‐Brown, NA Tehan, B DiMaio, F Jazayeri, A Robinson, CV Dürr, KL |
| author_sort | Chi, G |
| collection | OXFORD |
| description | Potassium‐coupled chloride transporters (KCCs) play crucial roles in regulating cell volume and intracellular chloride concentration. They are characteristically inhibited under isotonic conditions via phospho‐regulatory sites located within the cytoplasmic termini. Decreased inhibitory phosphorylation in response to hypotonic cell swelling stimulates transport activity, and dysfunction of this regulatory process has been associated with various human diseases. Here, we present cryo‐EM structures of human KCC3b and KCC1, revealing structural determinants for phospho‐regulation in both N‐ and C‐termini. We show that phospho‐mimetic KCC3b is arrested in an inward‐facing state in which intracellular ion access is blocked by extensive contacts with the N‐terminus. In another mutant with increased isotonic transport activity, KCC1Δ19, this interdomain interaction is absent, likely due to a unique phospho‐regulatory site in the KCC1 N‐terminus. Furthermore, we map additional phosphorylation sites as well as a previously unknown ATP/ADP‐binding pocket in the large C‐terminal domain and show enhanced thermal stabilization of other CCCs by adenine nucleotides. These findings provide fundamentally new insights into the complex regulation of KCCs and may unlock innovative strategies for drug development. |
| first_indexed | 2024-12-09T03:15:45Z |
| format | Journal article |
| id | oxford-uuid:12b8c667-5a24-4258-afb9-24478f959519 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-12-09T03:15:45Z |
| publishDate | 2021 |
| publisher | EMBO Press |
| record_format | dspace |
| spelling | oxford-uuid:12b8c667-5a24-4258-afb9-24478f9595192024-10-23T20:24:39ZPhospho‐regulation, nucleotide binding and ion access control in potassium‐chloride cotransportersJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:12b8c667-5a24-4258-afb9-24478f959519EnglishJisc Publications RouterEMBO Press2021Chi, GEbenhoch, RMan, HTang, HTremblay, LEReggiano, GQiu, XBohstedt, TLiko, IAlmeida, FGGarneau, APWang, DMcKinley, GMoreau, CPBountra, KDAbrusci, PMukhopadhyay, SMMFernandez‐Cid, ASlimani, SLavoie, JLBurgess‐Brown, NATehan, BDiMaio, FJazayeri, ARobinson, CVDürr, KLPotassium‐coupled chloride transporters (KCCs) play crucial roles in regulating cell volume and intracellular chloride concentration. They are characteristically inhibited under isotonic conditions via phospho‐regulatory sites located within the cytoplasmic termini. Decreased inhibitory phosphorylation in response to hypotonic cell swelling stimulates transport activity, and dysfunction of this regulatory process has been associated with various human diseases. Here, we present cryo‐EM structures of human KCC3b and KCC1, revealing structural determinants for phospho‐regulation in both N‐ and C‐termini. We show that phospho‐mimetic KCC3b is arrested in an inward‐facing state in which intracellular ion access is blocked by extensive contacts with the N‐terminus. In another mutant with increased isotonic transport activity, KCC1Δ19, this interdomain interaction is absent, likely due to a unique phospho‐regulatory site in the KCC1 N‐terminus. Furthermore, we map additional phosphorylation sites as well as a previously unknown ATP/ADP‐binding pocket in the large C‐terminal domain and show enhanced thermal stabilization of other CCCs by adenine nucleotides. These findings provide fundamentally new insights into the complex regulation of KCCs and may unlock innovative strategies for drug development. |
| spellingShingle | Chi, G Ebenhoch, R Man, H Tang, H Tremblay, LE Reggiano, G Qiu, X Bohstedt, T Liko, I Almeida, FG Garneau, AP Wang, D McKinley, G Moreau, CP Bountra, KD Abrusci, P Mukhopadhyay, SMM Fernandez‐Cid, A Slimani, S Lavoie, JL Burgess‐Brown, NA Tehan, B DiMaio, F Jazayeri, A Robinson, CV Dürr, KL Phospho‐regulation, nucleotide binding and ion access control in potassium‐chloride cotransporters |
| title | Phospho‐regulation, nucleotide binding and ion access control in potassium‐chloride cotransporters |
| title_full | Phospho‐regulation, nucleotide binding and ion access control in potassium‐chloride cotransporters |
| title_fullStr | Phospho‐regulation, nucleotide binding and ion access control in potassium‐chloride cotransporters |
| title_full_unstemmed | Phospho‐regulation, nucleotide binding and ion access control in potassium‐chloride cotransporters |
| title_short | Phospho‐regulation, nucleotide binding and ion access control in potassium‐chloride cotransporters |
| title_sort | phospho regulation nucleotide binding and ion access control in potassium chloride cotransporters |
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