ILDR1 and deafness: If the only role of angulin-2/ILDR1 in the cochlea is the recruitment of tricellulin to TCs, deafness with hair cell degeneration in Ildr1k-/- mice may be caused by impaired tTJ function because of the loss of tricellulin, which was shown to impair the barrier function of epithelial cellular sheets in vitro [7].