Mutant ubiquitin decreases amyloid β plaque formation in a transgenic mouse model of Alzheimer's disease

► UBB+1 modulates Aβ aggregation during the critical period of plaque formation. ► UBB+1 is ubiquitinated at K63 allowing nonsubstrate linked polyubiquitin chains. ► UBB+1 capped unanchored polyubiquitin chains may regulate the NF-κB pathway.