Endoplasmic reticulum–associated degradation of the renal potassium channel, ROMK, leads to type II Bartter syndrome

  title={Endoplasmic reticulum–associated degradation of the renal potassium channel, ROMK, leads to type II Bartter syndrome},
  author={Brighid M. O'Donnell and Timothy D. Mackie and Arohan R. Subramanya and Jeffrey L. Brodsky},
  journal={The Journal of Biological Chemistry},
  pages={12813 - 12827}
Type II Bartter syndrome is caused by mutations in the renal outer medullary potassium (ROMK) channel, but the molecular mechanisms underlying this disease are poorly defined. To rapidly screen for ROMK function, we developed a yeast expression system and discovered that yeast cells lacking endogenous potassium channels could be rescued by WT ROMK but not by ROMK proteins containing any one of four Bartter mutations. We also found that the mutant proteins were significantly less stable than WT… 

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