Recent Publication: Coffin, A. B., Dabdoud, A., Kelley, M. W., and Popper, A. N.
(2007). Myosin VI and VIIa distribution among inner ear
epithelia in diverse fishes. Hear. Res., 224:15-26.Link
All vertebrate inner
ears possess sensory hair cells. These cells transduce sound into
electrical impulses that are used by the nervous system. Although
these cells all share some basic features such as an apical hair
bundle and basal nerve synapses, there is much diversity in hair
cells, both within an organism and between vertebrate taxa. Our
lab studies this diversity as a means to understand hearing in general
and to examine evolutionary trends.
Current studies in the lab focus on unconventional
myosins, a group of motor proteins critical to hair cell structure
and function. Two of these proteins, myosins
VI and VIIa, have been implicated in hereditary deafness in
both humans and mice. We use immunocytochemistry to localize these
myosins in ears from diverse groups of fishes. Myosin antibodies
were kindly provided by Dr.
The figures on this page show a few examples of myosin VI distribution
in fish ears. Myosin labels are shown in red, and actin (the major
hair bundle protein) is shown in green.
Our studies show that
both of these proteins are present in hair cells of fishes, indicating
evolutionary conservation of these important molecules. We are currently
exploring differences in intracellular distribution of these proteins
that should shed further light on their function in hair cells.