Fig. 2.

β₁- and β₄-subunits are expressed in a gradient along the tonotopic axis of the basilar papilla. Transcript levels of β₁- and β₄-subunits expressed in successive quadrants of the tonotopic axis normalized to expression in the low frequency (LF) quadrant are shown. There is a decreasing amount of both transcripts from the LF to high-frequency (HF) ends of the papilla. The expression of both transcripts is also minimally changed across both middle-frequency (MF) quadrants (MF1 and MF2). The differences in expression between LF and both MF quadrants, MF and HF quadrants, and LF and HF quadrants are statistically significant (P < 0.01, ANOVA). Error bars are SD (n = 3).