Data Sheet 2_The role of NEDD4-mediated ubiquitination of AQP5 in allergic rhinitis: implications for nasal mucosal barrier function.pdf

We propose that the E3 ubiquitin ligase NEDD4 is responsible for the degradation of AQP5 and thus affects barrier homeostasis in AR.</p>Methods<p>Human nasal epithelial cells and ovalbumin-induced Sprague-Dawley rats were used as in vitro and in vivo models, respectively.

Control and AR groups were compared with siNEDD4 and ovAQP5 groups using co-immunoprecipitation, confocal microscopy, and ubiquitination assays to assess molecular interactions. Transepithelial electrical resistance (TER), MUC5AC secretion, and cytokine release were used to measure barrier function.</p>Results<p>We demonstrated that NEDD4 directly interacts with and ubiquitinates AQP5 at lysine 257, leading to its proteasomal degradation.