second harmonin_N_like domain (repeat 2) of the long isoform of whirlin, and related domains
This subgroup contains the second of two harmonin_N_like domains found in the long isoform of whirlin, and related domains. Whirlin is a postsynaptic density-95/discs-large/ZO-1 (PDZ) domain-containing scaffold protein which binds various components of the Usher protein network of the inner ear and the retina: erythrocyte protein p55, usherin, VlGR1, and myosin XVa. The long isoform of whirlin contains two harmonin_N_like domains, and three PDZ protein-binding domains, PDZ1-3. The short whirlin isoform, derived from an alternative start ATG, lacks the first harmonin_N_like domain but has in common with the long isoform, this second harmonin_N_like domain (designated repeat 2, included in this subgroup) and PDZ3. This second harmonin_N_like domain is a putative protein-binding module based on its sequence similarity to the N-terminal domain of harmonin.