Neural stem/progenitor cells (NSCs) reside in the subventricular zone (SVZ) and 
subgranular zone of the hippocampal dentate gyrus in adult mammals. The 
ubiquitin ligase HRD1 is associated with degradation of amyloid precursor 
protein and believed to be specifically expressed in neurons and not in 
astrocytes. We investigated expression of HRD1 using immunohistochemistry and 
found colocalization of HRD1 with the NSC marker protein nestin and glial 
fibrillary acidic protein in the NSCs of the SVZ (the SVZ astrocytes) but not in 
the hippocampus. In the hippocampal dentate gyrus, HRD1 is localized in the 
nucleus of nestin-positive cells.