Table 1.

Dynamics of tau-MT interaction: photobleaching analysis

GFP-tau23 GFP-tau24
Axonal shaft, single MT Growth cone, single MT Axonal shaft, MT bundle Fibroblast, single MT Fibroblast, cytoplasmic MT bundle Fibroblast, MT bundles in cell processes Axonal shaft, single MT Fibroblast, MT bundles in cell processes
T½ (seconds) 2.81±1.1 2.5±0.5 2.8±0.3 2.3±0.4 9.5±0.5 16.7±2.6 2.5±0.5 12.2±2.3
% Recovery 69.3±15.2 85±10.5 54.6±3.5 88±6.5 69.5±6.3 56.2±5.6 53±11.3 24.5±5.3
  • Background-subtracted fluorescence intensity of MTs after photobleaching as a function of time was fitted with a single exponential to obtain the t½ of fluorescence recovery and the percent of recovery (% recovery); the latter was calculated as a difference between fluorescence intensity immediately before photobleaching and that more than 5 minutes after photobleaching normalized to initial fluorescence. Values represent means±s.e.m. The number of experiments for each datum point varied from 15 to 20. No statistically significant difference was found between 3R-tau and 4R-tau in the dynamics of MT binding (P>0.05 for corresponding series of experiments).