BSND
Function
Regulatory subunit of anion-selective CLCNKA:BSND and CLCNKB:BSND heteromeric channels involved in basolateral chloride conductance along the nephron to achieve urine concentration and maintain systemic acid-base homeostasis, and in the stria vascularis of the inner ear to establish the endocochlear potential necessary for normal hearing (PubMed:11734858, PubMed:12111250, PubMed:12574213, PubMed:16849430, PubMed:18776122, PubMed:19646679, PubMed:20538786, PubMed:26013830). Most likely acts as a chaperone that allosterically regulates proper sorting of CLCNKA:BSND and CLCNKB:BSND channels at the basolateral plasma membrane domain and functional switch to ion conducting state. Mediates constitutive opening of channel common gates (PubMed:11734858, PubMed:12111250, PubMed:12574213, PubMed:16849430, PubMed:18776122, PubMed:19646679, PubMed:20538786, PubMed:26013830).
Involvement in disease
Bartter syndrome 4A, neonatal, with sensorineural deafness
BARTS4A
A form of Bartter syndrome, an autosomal recessive disorder characterized by impaired salt reabsorption in the thick ascending loop of Henle with pronounced salt wasting, hypokalemic metabolic alkalosis, and varying degrees of hypercalciuria. BARTS4A is associated with sensorineural deafness.
None
The disease is caused by variants affecting the gene represented in this entry.
Post-translational modifications
Palmitoylation is necessary for activation of plasma membrane-inserted CLC-K/barttin channels.
Tissue Specificity
Expressed primarily in kidney. Expressed in specific nephron segments and in the stria vascularis of the inner ear.
Cellular localization
- Basolateral cell membrane
- Multi-pass membrane protein
- Mostly sorted at the basolateral membrane. A significant amount also observed intracellularly. Staining in membranes of the renal tubule and of potassium-secreting epithelia of the inner ear is basolateral (By similarity).
Alternative names
BART, BSND, Barttin