Harp (harmonin-interacting, ankyrin repeat-containing protein), a novel protein that interacts with harmonin in epithelial tissues

Abstract

Mutations in the triple PDZ domain-containing protein harmonin have been identified as the cause of Usher deafness syndrome type 1C. Independently, we identified harmonin in a screen for genes expressed in pancreatic β cells. Using a yeast two-hybrid assay, we show that the first PDZ domain of harmonin interacts with a novel protein, designated harp for harmonin-interacting, ankyrin repeat-containing protein. This interaction was confirmed in an over-expression system and in mammalian cells, and shown to be mediated by the three C-terminal amino acids of harp. Harp is expressed in many of the same epithelia as harmonin and co-localization of native harp and harmonin was demonstrated by confo..