Figure 1
Overexpression of hTau reduces protein level of α4 nAChR with an increased cleavage of the receptor both in vitro and in vivo.
(a) Representative images of the cultured hippocampus neurons, the lenti-mCherry-hTau or the vector was infected at 7 DIV and the neurons were cultured for another 5 day (left), or the one-month-old rat brain hippocampus after bilateral ventricular infusion of AAV-GFP-hTau (2 μl each side, 1.5 μl/min speed) at postnatal day 0–1 (P0-1) (right). (b–d) Western blotting data show that overexpression of hTau reduced α4 nAChR level in 12 DIV primary hippocampus neurons (left, from 3 independent cultures; two-sample unpaired t test, t4 = 4.949, p = 0.0078), or in rat hippocampal CA3 extracts (right, from at least 3 rats; two-sample unpaired t test, t4 = 5.862, p = 0.0042). The red dotted lines show the bands of cleaved α4 nAChRs fragment (two-sample unpaired t test, t4 = 6.634, p = 0.0027 in c; t4 = 3.982, p = 0.0164 in d). (e,f) Overexpressing hTau in primary neurons (two-sample unpaired t test, t4 = 0.5740, p = 0.5967) or rat hippocampus (two-sample unpaired t test, t4 = 0.4220, p = 0.6906) did not affect mRNA level of α4 nAChR measured by real-time fluorescent quantitative PCR. Data were expressed as mean ± SEM, *p < 0.05, **p < 0.01 vs control.
