Abstract

Pannexin1 (Panx1) is a gap junction gene in vertebrates whose proteins mainly function as non-junctional channels on the cell surface. Panx1 channels can release ATP under physiological conditions and play critical roles in many physiological and pathological processes. Here, we report that Panx1 deficiency can reduce ATP release and endocochlear potential (EP) generation in the cochlea inducing hearing loss. Panx1 extensively expresses in the cochlea, including the cochlear lateral wall. We found that deletion of Panx1 in the cochlear lateral wall almost abolished ATP release under physiological conditions. Positive EP is a driving force for current through hair cells to produce auditory receptor potential. EP generation requires ATP. In the Panx1 deficient mice, EP and auditory receptor potential as measured by cochlear microphonics (CM) were significantly reduced. However, no apparent hair cell loss was detected. Moreover, defect of connexin hemichannels by deletion of connexin26 (Cx26) and Cx30, which are predominant connexin isoforms in the cochlea, did not reduce ATP release under physiological conditions. These data demonstrate that Panx1 channels dominate ATP release in the cochlea ensuring EP and auditory receptor potential generation and hearing. Panx1 deficiency can reduce ATP release and EP generation causing hearing loss.

Document Type

Article

Publication Date

6-2-2015

Notes/Citation Information

Published in Scientific Reports, vol. 5, article 10762, p. 1-10.

This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

Digital Object Identifier (DOI)

http://dx.doi.org/10.1038/srep10762

Funding Information

This work was supported by NIH (R01) DC 05989.

srep10762-s1.pdf (162 kB)
Supplementary Information

srep10762-f1.jpg (560 kB)
Figure 1: Panx1 deletion in the cochlea in Panx1 conditional knockout (cKO) mice.

srep10762-f2.jpg (160 kB)
Figure 2: Hearing loss in Panx1 cKO mice.

srep10762-f3.jpg (52 kB)
Figure 3: Reduction of EP in Panx1 cKO mice.

srep10762-f4.jpg (44 kB)
Figure 4: CM reduction in Panx1 cKO mice.

srep10762-f5.jpg (239 kB)
Figure 5: No substantial hair cell degeneration in Panx1 cKO mice.

srep10762-f6.jpg (39 kB)
Figure 6: Reduction of ATP release in the cochlea in Panx1 cKO mice.

srep10762-f7.jpg (245 kB)
Figure 7: Schematic drawing of EP generation with Panx1 ATP release in the cochlear lateral wall.

Share

COinS