Spatiotemporal expression of Ezh2 in the developing mouse cochlear sensory epithelium

Abstract

The enhancer of zeste 2 polycomb repressive complex 2 subunit (Ezh2) is a histone-lysine N-methyltransferase enzyme that participates in DNA methylation. Ezh2 has also been reported to play crucial roles in stem cell proliferation and differentiation. However, the detailed expression profile of Ezh2 during mouse cochlear development has not been investigated. Here, we examined the spatiotemporal expression of Ezh2 in the cochlea during embryonic and postnatal development. Ezh2 expression began to be observed in the whole otocyst nuclei at embryonic day 9.5 (E9.5). At E12.5, Ezh2 was expressed in the nuclei of the cochlear prosensory epithelium. At E13.5 and E15.5, Ezh2 was expressed from the apical to the basal turns in the nuclei of the differentiating cochlear epithelium. At postnatal day (P) 0 and 7, the Ezh2 expression was located in the nuclei of the cochlear epithelium in all three turns and could be clearly seen in outer and inner hair cells, supporting cells, the stria vascularis, and spiral ganglion cells. Ezh2 continued to be expressed in the cochlear epithelium of adult mice. Our results provide the basic Ezh2 expression pattern and might be useful for further investigating the detailed role of Ezh2 during cochlear development.

Keywords

polycomb repressive complex / Ezh2 / expression / inner ear / cochlea / development

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Acknowledgements

This work was supported by grants from the National Basic Research Program of China (973 Program, No. 2015CB965000), the National Natural Science Foundation of China (Nos. 81570911, 81470692, 81371094, 81230019, 81500790, 81570921, 31500852, and 31501194), the Jiangsu Province Natural Science Foundation (Nos. BK20150022, BK20140620, and BK20150598), the Fundamental Research Funds for the Central Universities (Nos. 2242014R30022 and 021414380037), the Yingdong Huo Education Foundation, and the Open Research Funds of the State Key Laboratory of Genetic Engineering, Fudan University (No. SKLGE-1407).

Compliance with ethics guidelines

Yan Chen, Wenyan Li, Wen Li, Renjie Chai, and Huawei Li declare that they have no conflict of interest. This manuscript does not contain any studies with human subjects performed by any of the authors.

RIGHTS & PERMISSIONS

2016 Higher Education Press and Springer-Verlag Berlin Heidelberg