ClC-4 (Chloride Channel Protein 4) is a voltage-gated chloride channel encoded by the CLCN4 gene. It is broadly expressed and localizes to endosomes and the plasma membrane, with important roles in kidney and brain.
| Attribute | Value |
|---|---|
| Protein Name | ClC-4 Chloride Channel |
| Gene | CLCN4 |
| UniProt | P51801 |
| PDB Structure | 6MGY |
| Molecular Weight | ~85 kDa |
| Subcellular Localization | Endosomes, plasma membrane |
| Protein Family | CLC chloride channel family |
ClC-4 is a member of the CLC chloride channel family, which consists of both chloride channels (ClC-1, ClC-2, ClC-6, ClC-7) and chloride/proton antiporters (ClC-3, ClC-4, ClC-5)1. Unlike some other CLC family members that are primarily plasma membrane channels, ClC-4 functions predominantly in intracellular organelles, particularly endosomes2.
ClC-4 shares the common CLC architecture:
The crystal structure of ClC-4 has been solved (PDB: 6MGY), revealing a dimeric architecture similar to other CLC family members3.
ClC-4 is expressed in multiple tissues:
In neurons, ClC-4 plays a role in regulating endosomal chloride homeostasis, which is critical for proper receptor trafficking and signaling4.
ClC-4 mutations have been associated with seizure disorders:
X-linked microphthalmia with linear skin defects (MLS) syndrome, caused by CLCN4 mutations, includes neurological manifestations:
Recent research suggests possible involvement of CLCN4 in Alzheimer's disease pathogenesis:
ClC-4 represents a potential therapeutic target for several conditions:
The CLCN4 gene is located on chromosome Xp22.2 and contains 12 exons. Pathogenic variants include:
ClC-4 interacts with several proteins and pathways:
ClC-4 knockout mice exhibit:
Zebrafish models with CLCN4 mutations show developmental abnormalities consistent with human MLS syndrome.
The study of Clc 4 Chloride Channel has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
Jentsch TJ & Pusch M. (2018). CLC chloride channels and transporters: from molecular proteins to disease. J Physiol, 596(11):1831-1848. DOI
Steinberg TH, et al. (2010). ClC-4 and ClC-5, a novel chloride channel family. Biochim Biophys Acta, 1798(4):665-671. DOI
Fischer M, et al. (2019). Structure of human CLC-4 in complex with a small molecule inhibitor. Nat Commun, 10:2475. DOI
Riazanski V, et al. (2015). ClC-3 channels in neuronal survival. J Biol Chem, 290(9):5512-5522. DOI
Suzuki T, et al. (2006). CLCN4 mutations in patients with X-linked microphthalmia. Invest Ophthalmol Vis Sci, 47(10):4123-4129. DOI
Stauber T, et al. (2012). The CLC-4 channel is endocytically processed. Traffic, 13(3):463-470. DOI
Wang Y, et al. (2020). Chloride channel CLC-4 promotes amyloidogenesis in Alzheimer's disease. Cell Death Dis, 11(10):852. DOI
Gu BJ, et al. (2022). A pathogenic ClC-4 variant leads to endosomal dysfunction and impaired neuronal development. Brain, 145(2):647-661. DOI