Fig. 3

Overexpressing tau activates the amino acid pathway which is upstream of the mTORC1. a Total and phosphorylated AKT and AMPK in HEK293T cells were measured by Western blotting, and the results showed that the phosphorylated level of AKT was significantly decreased in the tau-OE group (n = 9). b Increased levels of intercellular leucine (Leu), glutamic acid (Glu), alanine (Ala), and glycine (Gly) in the tau-OE group were detected by HPLC (n = 6). c Increased colocalization of LAMP1 (Red) and mTOR (Green) in the tau-OE group of HEK293T cells was detected by immunofluorescence staining, scale bar = 20 μm. The yellow arrow points to colocalization of LAMP1 and mTOR. AKT RAC serine/threonine protein kinase, AMPK AMP-activated protein kinase, GFP green fluorescent protein, LAMP1 lysosome-associated membrane glycoprotein 1, mTOR mammalian target of rapamycin kinase, Vec vector. All data are expressed as the mean ± SEM. ^*P < 0.05, ^**P < 0.01, ^***P < 0.001