Renal phosphate transporters are sodium-coupled transporters located in the apical membrane of proximal tubular cells. They play an important role in phosphate regulation.
Under physiological conditions phosphate is filtered in excess, so the body needs to reclaim large amounts of phosphate to keep the body content stable (60-80%). This resorption is accomplished by renal phosphate transporters. Inactivation of those transporters may result in excessive urinary phosphate loss and bone destruction ensue.
Renal phosphate transporters are located in the proximal tubule. The figure below shows its distribution along the segments. While the transporter SLC34A1 can be found in all three segments the other two are localized in the first two segments only.
Under physiological conditions theTrasnporter SLC20A2 has no effect on phosphate handling as dysfunction can be easily compensated by the other two transporters. Therefore no mutation with bone or kidney phenotype is known so far. However, it seems plausible that variation in this gene too may contribute to a phenotype caused by mutations in other genes.
|Hypophosphatemic bone and kindney disease|
|Disorders of the renal phosphate transporters|
|Hypophosphatemic rickets with hypercalciuria|
|Idiopathic basal ganglia calcification 1|
|Nephrolithiasis/osteoporosis, hypophosphatemic, 1|
|Nephrolithiasis/osteoporosis, hypophosphatemic, 2|
|FGF23-induced hypophosphatemic rickets|
|Fanconi-type hypophosphatemic rickets|
|Hypophosphatemic rickets with hyperparathyroidism|
|X-linked dominant hypophosphatemic rickets|
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