Module 10: Figure stereocilia Ca2+ signals
Visualization of the highly localized Ca2+ transient in a single stereocilium following mechanical deformation.
The diagonal white line in A marks the region that was scanned to create the line-scan image shown in B that ran for 500 ms (i.e. along the abscissa). Note the rapid increase in Ca2+ that began as soon as the tip was displaced by 200 nm for a period of 100 ms (time register at the top). The panels in C illustrate the time course of Ca2+ transients recorded at different points along the length of the stereocilium. It is clear that the microdomain was localized to the tip of the stereocilium (panels C2 and C4), and declined rapidly down the length of the stereocilium. Reproduced, with permission, from Lumpkin, E.A. and Hudspeth, A.J. (1998) Regulation of free Ca2+ concentration in hair-cell stereocilia. J. Neurosci. 18:6300–6318. Copyright (1998) by the Society for Neuroscience; see Lumpkin and Hudspeth 1998.