MAPT and Alzheimer disease: PDIA3 is also present in the cytosol, where it can interact, among other proteins, with the mammalian target of rapamycin (mTOR), which results up-regulated in selected neurons of AD brains that are predicted to develop tau pathology [21]; finally, PDIA3 is also present in the nucleus, where it can directly bind to DNA regions rich in A/T, regulating gene expression [22].