About Our Lab

Barr-Gillespie Lab: mouse utricle bundlesThe Barr-Gillespie Lab studies mechanoelectrical transduction by hair cells, the sensory cells of the inner ear. Hair-cell transduction is carried out by the hair bundle, a cluster of actin-rich stereocilia (green in image on left) and a single microtubule-based kinocilium (magenta). Bundles are polarized, so transduction is activated when the bundle is moved towards the tallest stereocilia. We are particularly interested in the molecules that are used to construct the hair bundle and those that compose the transduction apparatus. While our approach is highly interdisciplinary, we have pioneered the use of mass spectrometry to detect and measure hair bundle proteins. Visit our Projects page to find out more about ongoing research in the lab.

One Recent Discovery

In collaboration with Teresa Nicolson’s lab at OHSU, we have found that the transmembrane channel like proteins TMC1 and TMC2 interact with protocadherin 15 (PCDH15), a critical component of the tip link (Maeda et al., 2014). The TMCs have been hypothesized to be the long-sought-after mechanotransduction channel; whether or not that is true, they definitely contribute to the transduction complex. We are presently using immunoaffinity purification and mass spectrometry to characterize the components of the transduction complex.

Anatomy of a hair cell transduction complex