UCHL1 and Alzheimer disease: In this review, we have focused on several recent areas of new research: the role of ubiquitin C-terminal hydrolase L1 (Uch-L1), Ubiquitin-B+1 (UBB+1), F-box protein 2 (Fbxo2), and aggregation-promoting chaperones (CRAM-1 and MOAG-4) in Amyloid precursor protein (APP) and Aβ related metabolism as well as the related signaling pathways in AD and SCI, and discuss pressing questions in these fields of research.