ARHGEF9 and hereditary hyperekplexia: Surprisingly, although this system has been used to investigate GlyR α1 and α2 mutations in startle disease and NDDs (Zhang et al. 2016, 2017; Langlhofer et al. 2020; Chen et al. 2022) this unique system has not yet been used to assess the impacts of GlyR interacting proteins such as gephyrin/collybistin or syndapin I on GlyR trafficking, localization, peak amplitude, activation, and deactivation kinetics.