Fig. 1
From: Analysis of in vivo turnover of tau in a mouse model of tauopathy
Schematic illustration of regulatable tau transgenic mice and experimental design. a Illustration of tau transgene in pro-aggregant mice and anti-aggregant mice. b A schematic representation of in vivo microdialysis during doxycycline treatment. Human tau expression was suppressed by doxycycline in 16–17 month old pro-aggregant mice or anti-aggregant mice for a period indicated in the white box. ISF was collected for 2 days indicated in the gray box while doxycyline administration continued. The mean levels of ISF human tau were plotted against time indicated in arrows. Immediately after microdialysis experiments, the hippocampus was dissected (day of hippocampus collection). c Experimental scheme for collection of extracellular and intracellular tau in this study. Microdialysis probes with 1,000 kDa cut-off membranes were inserted in hippocampus to collect soluble extracellular tau in ISF. To measure intracellular tau, the hippocampus was homogenized in 3-step serial extraction with RAB, RIPA and 70 % Formic acid (FA) (See the details in methods section). d Tau5/HT7B ELISA specifically detects human tau. Tau levels in RAB fractions from Tau knockout mice (Tau KO) or wildtype mice or hTau mice were analyzed by Tau5/HT7B ELISA (n = 4/group, ****p < 0.0001). e HJ9.2/HJ8.7B ELISA specifically detects murine tau. Tau levels in RAB lysates from Tau knockout mice (Tau KO) or wildtype mice or hTau mice were analyzed by HJ9.2/HJ8.7B ELISA (n = 4/group, ****p < 0.0001). f Schematic diagram for calculation of half-life. Log-transformed values are fit with a linear regression and slope k’ was obtained from linear regression to calculate t1/2. Differences in slopes reflect alteration in clearance (white circles for faster clearance, black circles for slower clearance)