APP ubiquitination by VHL protein is essential for MVB sorting and lysosomal degradation.

Abstract

Amyloid precursor protein (APP), a type I transmembrane protein, is closely related to the pathogenesis of Alzheimer's disease (AD). Amyloid beta (Aβ) is generated by sequential processing of APP in the Golgi apparatus and endosomes, and its toxicity leads to neuron dysfunction and neurodegeneration. APP is selectively shuttled between intracellular membrane compartments and ultimately transported into lysosomes. However, the mechanisms underlying APP sorting signals and lysosomal degradation are largely unclear. In this study, we show that the von Hippel‒Lindau (VHL) protein, a subunit of an E3 ligase, recognizes the cytoplasmic domain of APP and mediates its ubiquitination. VHL-mediated ubiquitination facilitates the sorting of membrane APP into intraluminal vesicles of multivesicular bodies (MVBs) and subsequent degradation in lysosomes. Therefore, the loss of VHL accelerates Aβ plaque deposition and memory deficits in AD model mice. Our findings reveal the role of VHL in restricting AD pathogenesis through ubiquitination-dependent MVB sorting and lysosomal degradation of APP.