PSEN1 and Alzheimer disease: Along with the alteration in the syndapin-2 levels, an overexpression of Rab5 was found in the parenchymal fraction of APP-PS1, which confirms the previously reported overactivation of Rab5-positive endosomes in neurons of Alzheimer’s disease individuals.34,35 Other endocytic proteins, including clathrin, Rab7 and Rab11, were found to remain unaffected in the APP-PS1 mouse brains compared with WT.