Abstract
The aim of this work was to describe unique ultrastructural organization of the outer hair cell lateral wall. The molecular mechanism of electromotility is unknown but it is clear that the composition of plasma membrane, orientation of actin and spectrin molecules of
the cytoskeleton and interaction between them could be important for the electromotile response of outer hair cells. Active cochlear mechanisms amplify movement along the basilar membrane and transmit mechanical information to the inner hair cell, thus improving audio perception capabilities in mammals. Outer hair cells have a complex trilaminar lateral wall composed of plasma
membrane, highly organized cytoskeleton and subsurface cisternae, which form axial cylinders inserted into each other around the cell core. Recent discoveries have shown that a key component in the electromotility of outer hair cells is a motor protein prestin that is found in the cytoplasmic membrane of outer hair cells. Cytoskeleton nanostructure shows that it is not complete and uninterrupted, and is composed of separate domains, oriented to each other at different angles. Protein pillars are situated between the invaginations of the plasma membrane and actin filaments of the cytoskeleton. The innermost layer of the lateral cell is made up by subsurface cisternae associated with mitochondria