A scaffolding protein (552 aa) that will bundle actin filaments and has multiple PDZ domains. Harmonin forms complexes with cadherin-23 (CDH23, otocadherin) through two of the PDZ domains and the two are coexpressed in the stereocilia of hair cells and in photoreceptors in the retina. Harmonin anchors CDH23 to the microfilaments of the stereocilia. Mutations in harmonin are the cause of Usher's syndrome type 1C (USH1C), a rare, autosomal recessive syndrome of congenital deafness and progressive blindness; mutations in CDH23 are responsible for Usher's syndrome 1D. Mutations in harmonin are also responsible for autosomal recessive neurosensory deafness-18. Harmonin-interacting, ankyrin repeat-containing protein (HARP; 460 aa) is the human homologue of mouse SANS protein.
Subjects: Medicine and Health — Chemistry.