Structural highlights
Disease
CLCN3_HUMAN Non-specific syndromic intellectual disability. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry.
Function
CLCN3_HUMAN Strongly outwardly rectifying, electrogenic H(+)/Cl(-)exchanger which mediates the exchange of chloride ions against protons (By similarity). The CLC channel family contains both chloride channels and proton-coupled anion transporters that exchange chloride or another anion for protons (PubMed:29845874). The presence of conserved gating glutamate residues is typical for family members that function as antiporters (PubMed:29845874).[UniProtKB:P51791][1] Strongly outwardly rectifying, electrogenic H(+)/Cl(-)exchanger which mediates the exchange of chloride ions against protons.[2]
Publication Abstract from PubMed
The trafficking and activity of endosomes relies on the exchange of chloride ions and protons by members of the CLC family of chloride channels and transporters, whose mutations are associated with numerous diseases. Despite their critical roles, the mechanisms by which CLC transporters are regulated are poorly understood. Here, we show that two related accessory beta-subunits, TMEM9 and TMEM9B, directly interact with ClC-3, -4 and -5. Cryo-EM structures reveal that TMEM9 inhibits ClC-3 by sealing the cytosolic entrance to the Cl(-) ion pathway. Unexpectedly, we find that PI(3,5)P(2) stabilizes the interaction between TMEM9 and ClC-3 and is required for proper regulation of ClC-3 by TMEM9. Collectively, our findings reveal that TMEM9 and PI(3,5)P(2) collaborate to regulate endosomal ion homeostasis by modulating the activity of ClC-3.
Structural basis of ClC-3 inhibition by TMEM9 and PI(3,5)P(2).,Schrecker M, Son Y, Planells-Cases R, Kar S, Vorobeva V, Schulte U, Fakler B, Jentsch TJ, Hite RK bioRxiv [Preprint]. 2025 Mar 3:2025.02.28.640562. doi: 10.1101/2025.02.28.640562. PMID:40093093[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Jentsch TJ, Pusch M. CLC Chloride Channels and Transporters: Structure, Function, Physiology, and Disease. Physiol Rev. 2018 Jul 1;98(3):1493-1590. PMID:29845874 doi:10.1152/physrev.00047.2017
- ↑ Ogura T, Furukawa T, Toyozaki T, Yamada K, Zheng YJ, Katayama Y, Nakaya H, Inagaki N. ClC-3B, a novel ClC-3 splicing variant that interacts with EBP50 and facilitates expression of CFTR-regulated ORCC. FASEB J. 2002 Jun;16(8):863-5. PMID:11967229 doi:10.1096/fj.01-0845fje
- ↑ Schrecker M, Son Y, Planells-Cases R, Kar S, Vorobeva V, Schulte U, Fakler B, Jentsch TJ, Hite RK. Structural basis of ClC-3 inhibition by TMEM9 and PI(3,5)P(2). bioRxiv [Preprint]. 2025 Mar 3:2025.02.28.640562. PMID:40093093 doi:10.1101/2025.02.28.640562
