ATP8B1 is essential for maintaining normal hearing.
ATP8B1 deficiency is caused by autosomal recessive mutations in ATP8B1, which encodes the putative phospatidylserine flippase ATP8B1 (formerly called FIC1). ATP8B1 deficiency is primarily characterized by cholestasis, but extrahepatic symptoms are also found. Because patients sometimes report reduced hearing capability, we investigated the role of ATP8B1 in auditory function. Here we show that ATP8B1/Atp8b1 deficiency, both in patients and in Atp8b1(G308V/G308V) mutant mice, causes hearing loss, associated with progressive degeneration of cochlear hair cells. Atp8b1 is specifically localized in the stereocilia of these hair cells. This indicates that the mechanosensory function and integrity of the cochlear hair cells is critically dependent on ATP8B1 activity, possibly through maintaining lipid asymmetry in the cellular membranes of stereocilia.
Stapelbroek
Janneke M
JM
Department of Pediatric Gastroenterology, University Medical Center Utrecht, Utrecht, The Netherlands. jstapelb@umcutrecht.nl
Peters
Theo A
TA
van Beurden
Denis H A
DH
Curfs
Jo H A J
JH
Joosten
Anneke
A
Beynon
Andy J
AJ
van Leeuwen
Bibian M
BM
van der Velden
Lieke M
LM
Bull
Laura
L
Oude Elferink
Ronald P
RP
van Zanten
Bert A
BA
Klomp
Leo W J
LW
Houwen
Roderick H J
RH
D000251:Adenosine Triphosphatases / Q000235:genetics / Q000502:physiology*; D000818:Animals; D006309:Hearing / Q000502:physiology*; D006319:Hearing Loss, Sensorineural / Q000235:genetics / Q000503:physiopathology; D006801:Humans; D051379:Mice; D008817:Mice, Mutant Strains; D009925:Organ of Corti / Q000473:pathology; D049294:Phospholipid Transfer Proteins
D049294:Phospholipid Transfer Proteins; D000251:Adenosine Triphosphatases; C111067:ATP8B1 protein, human; C491742:Atp8b1 protein, mouse