Article
Cell Biology
Maryna Ivanchenko, Artur A. Indzhykulian, David P. Corey
Summary: Hair cells in the vertebrate inner ear have actin-filled protrusions called stereocilia which mediate mechanosensitivity. Hereditary deafness is often linked to abnormalities in stereocilia bundles, making them essential for understanding genetic hearing loss models. Electron microscopy techniques, such as TEM and SEM, are crucial for studying stereocilia morphology and protein localization.
FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY
(2021)
Article
Biology
Elizabeth L. Wagner, Jun-Sub Im, Stefano Sala, Maura Nakahata, Terence E. Imbery, Sihan Li, Daniel Chen, Katherine Nimchuk, Yael Noy, David W. Archer, Wenhao Xu, George Hashisaki, Karen Avraham, Patrick Oakes, Jung-Bum Shin
Summary: Prolonged exposure to loud noise can damage inner ear sensory hair cells, resulting in gaps in the stereocilia core. Newly synthesized actin helps repair these gaps within a week of traumatic noise exposure, with Xin actin binding repeat containing 2 (XIRP2) playing a crucial role in the repair process and facilitating the enrichment of monomeric β-actin at the gaps. XIRP2 recruitment to stereocilia gaps and stress fiber strain sites is force-dependent and mediated by a mechanosensor domain in its C-terminus. This novel process may contribute to recovery from temporary hearing threshold shifts and the prevention of age-related hearing loss.
Article
Cell Biology
Keji Yan, Wen Zong, Haibo Du, Xiaoyan Zhai, Rui Ren, Shuang Liu, Wei Xiong, Yanfei Wang, Zhigang Xu
Summary: In this study, it was found that BAIAP2L2 is localized at the tips of inner ear hair cells' stereocilia, and its inactivation leads to degeneration of mechanotransducing stereocilia, resulting in hearing loss. BAIAP2L2 binds to components of the row 2 complex and MET complex, indicating its crucial role in maintaining stereocilia.
JOURNAL OF CELLULAR PHYSIOLOGY
(2022)
Review
Pharmacology & Pharmacy
V. B. Dugina, G. S. Shagieva, P. B. Kopnin
Summary: Cytoplasmic actin isoforms play important roles in cellular processes and their imbalances are linked to pathology. Understanding the underlying mechanisms is relevant for both basic research and clinical applications. Study of actin diversity and function in cancer may contribute to treatment strategies.
FRONTIERS IN PHARMACOLOGY
(2022)
Review
Cell Biology
Joseph A. Cirilo, Laura K. Gunther, Christopher M. Yengo
Summary: Cytoskeletal motors, particularly myosins, play crucial roles in various mechanical functions in cells, such as muscle contraction and cargo transport. Class III myosins, MYO3A and MYO3B, have been shown to regulate stereocilia lengths in auditory and vestibular inner ear hair cells, with mutations in these myosins leading to hearing loss. Research on these myosins and other stereocilia-associated myosins is important and may lead to novel therapeutic strategies for the treatment of hearing loss.
FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY
(2021)
Article
Neurosciences
Xiaoying Wang, Shuang Liu, Qi Cheng, Chengli Qu, Rui Ren, Haibo Du, Nana Li, Keji Yan, Yanfei Wang, Wei Xiong, Zhigang Xu
Summary: The protein complex known as mechanoelectrical transduction (MET) in inner-ear hair cells is crucial for hearing and balance perception. Calcium and integrin-binding protein 2 (CIB2) is a component of the MET complex and its absence leads to total loss of MET currents in auditory hair cells and profound hearing loss. This study reveals that CIB2 and CIB3 redundantly regulate MET in vestibular hair cells, and their simultaneous loss abolishes MET currents and causes severe balance deficits. CIB2 and CIB3 also play distinct roles in stereocilia maintenance in different regions of vestibular hair cells.
JOURNAL OF NEUROSCIENCE
(2023)
Article
Cell Biology
Haibo Du, Hao Zhou, Yixiao Sun, Xiaoyan Zhai, Zhengjun Chen, Yanfei Wang, Zhigang Xu
Summary: CDC42 plays a pivotal role in regulating hair cell stereocilia development in the inner ear, and deficits in this process may lead to hearing or balancing disorders.
FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY
(2021)
Article
Audiology & Speech-Language Pathology
Jinho Park, Jonathan E. Bird
Summary: Hair cells in the inner ear assemble mechanosensitive hair bundles that transduce sounds and accelerations. The actin cytoskeleton and actin-binding proteins play crucial roles in the formation and function of these hair bundles. Disruption of these processes can lead to hereditary hearing loss. This review provides an overview of the actin-based structures in the hair bundle and the molecules involved, as well as recent advances in understanding the mechanisms of stereocilia elongation and their regulation by mechanoelectrical transduction.
Article
Biochemistry & Molecular Biology
Anton S. Shakhov, Polina A. Kovaleva, Alexandra S. Churkina, Igor I. Kireev, Irina B. Alieva
Summary: Actin cytoskeleton is crucial for cellular processes, and there are different isoforms in non-muscle cells, β-actin and γ-actin, which have distinct functions and localization in the cytoplasm. Based on super-resolution microscopy, this study demonstrates that β-actin and γ-actin are segregated in the cytoplasm of endothelial cells, with varying degrees of colocalization in different cellular regions. The segregation of actin isoforms is enhanced during the activation of cell lamella in endothelial barrier dysfunction.
Article
Neurosciences
Alix Trouillet, Katharine K. Miller, Shefin Sam George, Pei Wang, Noor-E-Seher Ali, Anthony Ricci, Nicolas Grillet
Summary: The study identified the importance of the Loxhd1/DFNB77 gene in the mechanotransduction process in cochlear hair cells. Mutations in Loxhd1 in mice resulted in mechanotransduction defects without morphological defects or reduction in tip link number. These findings revealed a novel LOXHD1-dependent step in hair bundle development critical for mechanotransduction in mature hair cells and normal hearing function in mice and humans.
JOURNAL OF NEUROSCIENCE
(2021)
Article
Neurosciences
Antonia Gonzalez-Garrido, Remy Pujol, Omar Lopez-Ramirez, Connor Finkbeiner, Ruth Anne Eatock, Jennifer S. Stone
Summary: Regenerated vestibular hair cells in adult mice show similarities to mature type II hair cells, but fail to fully recapture the properties of normal cells, displaying some characteristics of immature cells. Limitations in total cell number, cell type diversity, and extent of cellular differentiation suggest that interventions may be needed to promote full regeneration with potential for vestibular function recovery.
JOURNAL OF NEUROSCIENCE
(2021)
Article
Cell Biology
Jinan Li, Chang Liu, Bo Zhao
Summary: The interaction between GRXCR2 and CLIC5 at the base of stereocilia is crucial for normal hearing. While GRXCR2 does not affect the localization of CLIC5 during development, mice with an in-frame deletion in Grxcr2 exhibit hearing loss, indicating the importance of GRXCR2 and CLIC5 interaction in auditory perception.
FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY
(2021)
Article
Multidisciplinary Sciences
Andrew A. Mecca, Giusy A. Caprara, Anthony W. Peng
Summary: This study found that up-regulation of cAMP lowers the sensitivity of the channel by decreasing the stiffness of the gating spring. Prolonged depolarization can also mimic the effects of cAMP. The results suggest that cAMP signaling modulates gating spring stiffness to affect auditory sensitivity.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Neurosciences
Keji Yan, Chengli Qu, Yanfei Wang, Wen Zong, Zhigang Xu
Summary: Hair cells in the inner ear are responsible for hearing and balance. The role of BAIAP2L2 in vestibular hair cell stereocilia development and maintenance was examined, and it was found that BAIAP2L2 inactivation does not affect these processes.
FRONTIERS IN MOLECULAR NEUROSCIENCE
(2022)
Article
Cell Biology
Nana Li, Yuehui Xi, Haibo Du, Hao Zhou, Zhigang Xu
Summary: The study suggests that ANXA4 is dispensable for the development and function of hair cells, as shown by knockout experiments indicating limited impact on cochlear and vestibular hair cells.
FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY
(2021)