Lysakowski Anna, Govindaraju Aravind Chenrayan, Raphael Robert M
Department of Anatomy and Cell Biology, University of Illinois at Chicago, 808 S. Wood St., M/C 512, Chicago, IL 60605, USA.
Applied Physics Graduate Program, Department of Bioengineering, Rice University, Houston, TX, USA.
Hear Res. 2022 Dec;426:108612. doi: 10.1016/j.heares.2022.108612. Epub 2022 Sep 20.
Mitochondria supply energy in the form of ATP to drive a plethora of cellular processes. In heart and liver cells, mitochondria occupy over 20% of the cellular volume and the major need for ATP is easily identifiable - i.e., to drive cross-bridge recycling in cardiac cells or biosynthetic machinery in liver cells. In vestibular and cochlear hair cells the overall cellular mitochondrial volume is much less, and mitochondria structure varies dramatically in different regions of the cell. The regional demands for ATP and cellular forces that govern mitochondrial structure and localization are not well understood. Below we review our current understanding of the heterogeneity of form and function in hair cell mitochondria. A particular focus of this review will be on regional specialization in vestibular hair cells, where large mitochondria are found beneath the cuticular plate in close association with the striated organelle. Recent findings on the role of mitochondria in hair cell death and aging are covered along with potential therapeutic approaches. Potential avenues for future research are discussed, including the need for integrated computational modeling of mitochondrial function in hair cells and the vestibular afferent calyx.
线粒体以三磷酸腺苷（ATP）的形式提供能量，以驱动大量细胞过程。在心脏和肝脏细胞中，线粒体占据细胞体积的20%以上，对ATP的主要需求很容易确定——即驱动心肌细胞中的横桥循环或肝细胞中的生物合成机制。在前庭和耳蜗毛细胞中，细胞内线粒体的总体积要小得多，并且线粒体结构在细胞的不同区域有很大差异。对ATP的区域需求以及控制线粒体结构和定位的细胞力尚未得到很好的理解。下面我们回顾一下目前对毛细胞线粒体形态和功能异质性的理解。本综述的一个特别重点将是前庭毛细胞的区域特化，在那里可以在角质板下方发现与横纹细胞器紧密相连的大型线粒体。文中还涵盖了线粒体在毛细胞死亡和衰老中的作用的最新发现以及潜在的治疗方法。讨论了未来研究的潜在途径，包括对毛细胞和前庭传入花萼中线粒体功能进行综合计算建模的必要性。
