Ratzan Evan M, Lee John, Madison Margot A, Zhu Hong, Zhou Wu, Géléoc Gwenaëlle S G, Holt Jeffrey R
Department of Otolaryngology, F.M. Kirby Neurobiology Center, Boston Children's Hospital and Harvard Medical School, Boston, MA, United States.
Department of Otolaryngology - Head and Neck Surgery, University of Mississippi Medical Center, Jackson, MS, United States.
Front Neurol. 2024 Apr 4;15:1356614. doi: 10.3389/fneur.2024.1356614. eCollection 2024.
and are essential pore-forming subunits of mechanosensory transduction channels localized to the tips of stereovilli in auditory and vestibular hair cells of the inner ear. To investigate expression and function of and in vestibular organs, we used quantitative polymerase chain reaction (qPCR), fluorescence in situ hybridization - hairpin chain reaction (FISH-HCR), immunostaining, FM1-43 uptake and we measured vestibular evoked potentials (VsEPs) and vestibular ocular reflexes (VORs). We found that and showed dynamic developmental changes, differences in regional expression patterns, and overall expression levels which differed between the utricle and saccule. These underlying changes contributed to unanticipated phenotypic loss of VsEPs and VORs in KO mice. In contrast, KO mice retained VsEPs despite the loss of the calcium buffering protein calretinin, a characteristic biomarker of mature striolar calyx-only afferents. Lastly, we found that neonatal gene replacement therapy is sufficient to restore VsEP in KO mice for up to six months post-injection.
和是机械感觉转导通道的重要孔形成亚基，定位于内耳听觉和前庭毛细胞的静纤毛尖端。为了研究和在前庭器官中的表达和功能，我们使用了定量聚合酶链反应（qPCR）、荧光原位杂交-发夹链反应（FISH-HCR）、免疫染色、FM1-43摄取，并测量了前庭诱发电位（VsEPs）和前庭眼反射（VORs）。我们发现和表现出动态发育变化、区域表达模式差异以及椭圆囊和球囊之间的整体表达水平差异。这些潜在变化导致了KO小鼠中VsEPs和VORs出现意外的表型丧失。相比之下，KO小鼠尽管失去了钙缓冲蛋白钙视网膜蛋白（成熟的仅纹状萼传入神经的特征性生物标志物），仍保留了VsEPs。最后，我们发现新生基因替代疗法足以在注射后长达六个月的时间内恢复KO小鼠的VsEP。
