In a study with heterologous cell plasmid transfection, choline acetyltransferase activity, directly leading to ligand binding regulation, proves a prerequisite for α9α10 nAChR assembly and membrane stabilization, while transmembrane proteins associated with hearing loss like TMIE or TIMEM132e serve as auxiliary subunits for channel gating [52]. This evidence concerns the gene CHRNA4 and hearing loss disorder.