BAIAP2L2 Inactivation Does Not Affect Stereocilia Development or Maintenance in Vestibular Hair Cells

Frontiers in Molecular Neuroscience

Zhigang Xu¹  Chengli Qu²  Keji Yan²  Yanfei Wang²  Wen Zong³ 

[1] Shandong Provincial Collaborative Innovation Center of Cell Biology, Shandong Normal University, Jinan, China;Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China;State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China;

关键词: inner ear;    vestibular hair cells;    stereocilia;    BAIAP2L2;    CAPZB2;   

DOI  :  10.3389/fnmol.2022.829204

来源: DOAJ

【 摘 要 】

Hair cells are mechanosensitive cells in the inner ear, characterized by dozens to hundreds of actin-based stereocilia and one tubulin-based kinocilium on the apical surface of each cell. Two types of hair cells, namely cochlear hair cells and vestibular hair cells (VHCs), are responsible for the sensation of sound and balancing information, respectively. In each hair cell, the stereocilia are organized into rows of increasing heights with the mechano-electrical transduction (MET) channels localized at the tips of shorter-row stereocilia. A so-called “row 2 protein complex” also localizes at the tips of shorter-row mechanotransducing stereocilia, which plays important roles in the maintenance of mechanotransducing stereocilia. Recently, we and others identified BAIAP2L2 as a new component of row 2 complex. Baiap2l2 inactivation causes degeneration of the mechanotransducing stereocilia in cochlear hair cells, and leads to profound hearing loss in mice. In the present work, we examined the role of BAIAP2L2 in the VHC stereocilia. Confocal microscopy reveals that BAIAP2L2 immunoreactivity is localized at the tips of shorter-row stereocilia in VHCs. However, stereocilia development and maintenance are unaffected in Baiap2l2–/– VHCs. Meanwhile, MET function of VHCs as well as vestibular functions are also unaffected in Baiap2l2–/– mice. Further investigations show that the stereociliary tip localization of CAPZB2, another known row 2 complex component, is not affected in Baiap2l2–/– VHCs, consistent with the unaltered stereocilia morphology. Taken together, our present data show that BAIAP2L2 inactivation does not affect vestibular hair cell stereocilia.

【 授权许可】

Unknown