USH1 protein network component sans (USH1G)

USH1 protein network component sans (USH1G) is a scaffold protein containing multiple protein-binding domains, including ankyrin repeats and a sterile alpha motif (SAM) domain, which allow it to mediate the assembly of multi-protein complexes essential for inner ear hair cell and retinal photoreceptor function[3][5]. It forms a critical part of the Usher syndrome protein network, physically linking and stabilizing other USH1 proteins (such as harmonin/USH1C, cadherin 23, and myosin VIIa) that are necessary for mechanosensory transduction in hair cells and photoreceptors in the retina[1][3]. Recent findings show USH1G/SANS also regulates pre-mRNA splicing by mediating the intra-nuclear transfer and recycling of spliceosomal components, indicating a nuclear function besides its defined role in ciliary structures[3]. Mutations in USH1G cause Usher syndrome type 1G, the most severe form of hereditary deaf-blindness, due to progressive degeneration of auditory and visual sensory cells[1][3][5]. No therapeutic drugs are known to selectively target USH1G, and it is primarily studied as a disease gene/protein rather than as a tractable pharmacological target[3]. Key structural features: - N-terminal ankyrin repeats - Central (CENT) domain with numerous binding partners - C-terminal SAM domain and a PDZ-binding motif for scaffold activity[5] USH1G does not belong to classic receptor, enzyme, transporter, ion channel, or transcription factor families, but is classified as a scaffold/adaptor protein essential for the cell biology of specialized sensory cells[3][5].

Other names

SANSScaffold protein containing ankyrin repeats and SAM domainpre-mRNA splicing regulator USH1GUsher syndrome type-1G proteinANKS4AFLJ33924Usher syndrome 1G (autosomal recessive)