Fig. 2: PMCA1 channel expression level along the cochlea and auditory function in Pmca1 CKO mice.

A–C Gradient expression of PMCA1 in IHCs. Immunofluorescence images of PMCA1 (green) and ribbon synapses (red) in the low-frequency (A), high-frequency (B) regions, with corresponding quantification of the PMCA1 fluorescence intensity ratio (C). D–E The expression of PMCA1 proteins from apex- and base- basilar membrane was quantified by western blot. Three samples (2 cochlear from same mouse pooled for each sample) were used for immunoblot analysis. F Strategy for conditional knockout of Pmca1 in hair cells, depicting LoxP sites inserted to flank exon 9. G Cochlear whole-mounts immunostaining with anti-Myosin VIIA antibody (red) to label hair cells and stained with anti-PMCA1 antibody to detect PMCA1 protein (green). H–J ABR thresholds are elevated in Pmca1 CKO mice, compared with WT controls. Progression of hearing loss is seen in Pmca1 CKO mice from P12, P18 and P24. K, L Representative capacitance traces (K) and quantification of ΔC_m (L) evoked by 20 ms and 200 ms depolarizations in IHCs from mice of different ages, showing the functional consequence of impaired calcium clearance. Statistical analysis by two-side unpaired t test or Mann-Whitney test with significance indicated and two-way ANOVA followed by the Bonferroni post hoc test with significance indicated. All data, the number of data, statistical test used and p values can be found in the source data file. N.S., not significant, *p < 0.05; **p < 0.01; ***p < 0.001.