Fig. 4. Severe hearing loss in Prestin^Cre/+Atg7^flox/flox mice.

A ABR click thresholds showed a 40-dB gap between two mice groups. B At P30, the hearing thresholds of Prestin^Cre/+Atg7^flox/flox mice were >70 dB on average. C At P60, the average ABR hearing thresholds of Prestin^Cre/+Atg7^flox/flox mice were elevated to >75 dB. D At P90, the ABR hearing thresholds were around 83 dB for the knockout mice. E, F DPOAE traces with 2F1 − F2 measured as a function of frequency F2. The strongest response was around 10 kHz at the F2 frequency for Prestin^Cre/+Atg7^flox/flox mice. At P30, the DPOAE of the Atg7-deficient mice was suppressed at frequencies >6 kHz, with an overall average shift of >11 dB. At P60, the difference between the two groups approached 15 dB on average. DPOAE was almost absent at around ≥12 kHz. N = 12 for each group.