High-resolution SEM analysis of tip links.
(a, b) Control hair bundles had moderate levels of bundle Fluo-4 fluorescence and many tip links at their stereocilia tips (c, d; orange arrowheads point to tip links). (e, f) Bundles treated with 5 mM EGTA for 5 min showed a marked decrease in bundle Fluo-4 fluorescence and a significant reduction in the number of tip links (g, h). Red stars in e and f highlight cell body Fluo-4 fluorescence. (i) Tip links were quantified by dividing the number of tip links in a bundle by the number of observable tip link positions (**** p<0.0001). Scale bars in a and e are 10 µm, c and g are 1 µm, and d and h are 0.5 µm.