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Annexin A4 Is Dispensable for Hair Cell Development and Function
Nana Li1, Yuehui Xi1, Haibo Du1
1Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China.
Frontiers in Cell and Developmental Biology
|June 21, 2021
Summary
Annexin A4 (ANXA4) is not essential for the development or function of cochlear and vestibular hair cells. Its absence did not affect hair cell structure, mechano-electrical transduction, or auditory and vestibular functions in knockout mice.
Area of Science:
- Cell Biology
- Neuroscience
- Genetics
Background:
- Annexin A4 (ANXA4) is a calcium-dependent phospholipid-binding protein.
- ANXA4 is specifically expressed in cochlear and vestibular hair cells, but its function is unknown.
Purpose of the Study:
- To investigate the role of ANXA4 in hair cell development and function.
- To determine if ANXA4 is essential for auditory and vestibular sensory processes.
Main Methods:
- Generated Anxa4 knockout mice using CRISPR/Cas9 gene editing.
- Assessed hair cell development, stereocilia morphology, mechano-electrical transduction (MET), and auditory/vestibular function in knockout mice.
Main Results:
- Anxa4 knockout mice exhibited normal cochlear and vestibular hair cell development.
- Stereocilia morphology, MET function, and auditory/vestibular functions remained normal in the absence of ANXA4.
- ANXA4 protein was localized to the plasma membrane and stereocilia tips of hair cells.
Conclusions:
- ANXA4 is dispensable for hair cell development and function.
- Functional redundancy with other annexins may explain the lack of phenotype in Anxa4 knockout mice.
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