  Avian prestin is sensitive to membrane thickness as much as mammalian
prestin, which undergoes conformational transitions in membrane area and
thereby drives length changes of the cylindrical cell body of outer hair cells.
The membrane thickness dependence of mammalian prestin stems from changes in
hydrophobic profile in conformational states, accompanied by changes in their
membrane area. Even though such area changes are not detected for avian
prestin, it nonetheless bends hair bundles of avian short hair cells. Here it
is suggested that the motile function of avian prestin can be based on
conformational transitions involving shearing deformation of the membrane
protein, which also leads to membrane thickness sensitivity.
