Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report | Ligand Interaction | Predict Membrane 

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly Evidence: gel filtration, native gel electrophoresis

Macromolecule Content

• Total Structure Weight: 246.30 kDa 
• Atom Count: 13400 
• Modelled Residue Count: 1758 
• Deposited Residue Count: 2200 
• Unique protein chains: 1

6Y5V

Structure of Human Potassium Chloride Transporter KCC3b (S45D/T940D/T997D) in KCl

• PDB DOI: 10.2210/pdb6Y5V/pdb
• EM Map EMD-10704:EMDBEMDataResource

• Classification: MEMBRANE PROTEIN
• Organism(s): Homo sapiens
• Expression System: Homo sapiens
• Mutation(s): No 
• Membrane Protein: Yes  OPMPDBTMmpstruc


• Deposited: 2020-02-25 Released: 2020-07-15 
• Deposition Author(s): Chi, G., Man, H., Ebenhoch, R., Reggiano, G., Pike, A.C.W., Wang, D., McKinley, G., Mukhopadhyay, S.M.M., MacLean, E.M., Chalk, R., Moreau, C., Snee, M., Bohstedt, T., Singh, N.K., Abrusci, P., Arrowsmith, C.H., Bountra, C., Edwards, A.M., Marsden, B.D., Burgess-Brown, N.A., DiMaio, F., Duerr, K.L.
• Funding Organization(s): European Commission

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 4.08 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Phospho-regulation, nucleotide binding and ion access control in potassium-chloride cotransporters.

Chi, G., Ebenhoch, R., Man, H., Tang, H., Tremblay, L.E., Reggiano, G., Qiu, X., Bohstedt, T., Liko, I., Almeida, F.G., Garneau, A.P., Wang, D., McKinley, G., Moreau, C.P., Bountra, K.D., Abrusci, P., Mukhopadhyay, S.M.M., Fernandez-Cid, A., Slimani, S., Lavoie, J.L., Burgess-Brown, N.A., Tehan, B., DiMaio, F., Jazayeri, A., Isenring, P., Robinson, C.V., Durr, K.L.

(2021) EMBO J 40: e107294-e107294

• PubMed: 34031912 
• DOI: 10.15252/embj.2020107294
• Primary Citation of Related Structures:  
  6Y5V, 7AIN, 7AIO, 7AIP, 7AIQ, 7AIR, 7NGB


• PubMed Abstract: 
  

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.

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Organizational Affiliation: 

OMass Therapeutics, Ltd., Oxford, UK.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Solute carrier family 12 member 6	A, B	1100	Homo sapiens	Mutation(s): 0  Gene Names: SLC12A6, KCC3 Membrane Entity: Yes
UniProt & NIH Common Fund Data Resources
Find proteins for Q9UHW9 (Homo sapiens) Explore Q9UHW9  Go to UniProtKB:  Q9UHW9
PHAROS:  Q9UHW9 GTEx:  ENSG00000140199

Oligosaccharides

Help

Entity ID: 2
Molecule	Chains	Chain Length	2D Diagram	Glycosylation
beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose	C, D	3		N-Glycosylation
Glycosylation Resources
GlyTouCan:  G15407YE GlyCosmos:  G15407YE GlyGen:  G15407YE

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
NAG	E [auth A], F [auth B]	2-acetamido-2-deoxy-beta-D-glucopyranose C8 H15 N O6 OVRNDRQMDRJTHS-FMDGEEDCSA-N

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 4.08 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2020-02-25 
• Released Date: 2020-07-15 
Deposition Author(s): Chi, G., Man, H., Ebenhoch, R., Reggiano, G., Pike, A.C.W., Wang, D., McKinley, G., Mukhopadhyay, S.M.M., MacLean, E.M., Chalk, R., Moreau, C., Snee, M., Bohstedt, T., Singh, N.K., Abrusci, P., Arrowsmith, C.H., Bountra, C., Edwards, A.M., Marsden, B.D., Burgess-Brown, N.A., DiMaio, F., Duerr, K.L.

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Funding Organization	Location	Grant Number
European Commission	United Kingdom	115766

Revision History  

• Version 1.0: 2020-07-15
  Type: Initial release
  
• Version 2.0: 2020-07-29
  Type: Remediation
  Reason: Carbohydrate remediation
  Changes: Atomic model, Data collection, Derived calculations, Structure summary
• Version 2.1: 2021-06-09
  Changes: Database references, Structure summary
• Version 2.2: 2021-07-28
  Changes: Database references