Myosin Light-Chain Kinase Is Necessary for Membrane Homeostasis in Cochlear Inner Hair Cells
Figure 1
MLCK expression in mouse cochleae.
(A) Upper panel: Western blot analyses demonstrate that S-MLCK (short MLCK) is expressed in mouse cochleae. Samples of 25 µg of cochlear protein were separated on 5% SDS-PAGE. The K36 antibody was used as the primary antibody. The results showed one band of approximately 130–140 kD (short MLCK should be 108 kD). Lower panel: Quantitative analysis of Mylk gene expression in MLCKIKO (solid symbol) and CTR (open symbol) mice. The bars represent the means of IODS-MLCK/IODβactin ±SD (integral optical density, IOD). The * symbols denote statistical significance at the level of P<0.05 vs CTR. (B) Whole-mount in situ hybridization for Mylk RNA in the inner ear. Mylk mRNA is expressed predominantly in the stria vascularis (arrowhead) and is moderately expressed in the organ of Corti (arrow). (C) Immunochemistry of K36 (red) in cross-sections of cochleae from wild-type mice. The nuclei were stained (blue) with Topro. (D) High-magnification view of the organ of Corti. S-MLCK: short MLCK; CO, the organ of Corti; SV, scala vestibuli; SM, scala media; ST, scala tympani; IHC, inner hair cell.