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Pulse-Chase Proteomics of the App Knockin Mouse Models of Alzheimer's Disease Reveals that Synaptic Dysfunction Originates in Presynaptic Terminals.

ABSTRACT: Compromised protein homeostasis underlies accumulation of plaques and tangles in Alzheimer's disease (AD). To observe protein turnover at early stages of amyloid beta (A?) proteotoxicity, we performed pulse-chase proteomics on mouse brains in three genetic models of AD that knock in alleles of amyloid precursor protein (APP) prior to the accumulation of plaques and during disease progression. At initial stages of A? accumulation, the turnover of proteins associated with presynaptic terminals is selectively impaired. Presynaptic proteins with impaired turnover, particularly synaptic vesicle (SV)-associated proteins, have elevated levels, misfold in both a plaque-dependent and -independent manner, and interact with APP and A?. Concurrent with elevated levels of SV-associated proteins, we found an enlargement of the SV pool as well as enhancement of presynaptic potentiation. Together, our findings reveal that the presynaptic terminal is particularly vulnerable and represents a critical site for manifestation of initial AD etiology. A record of this paper's transparent peer review process is included in the Supplemental Information.

SUBMITTER: Hark TJ

PROVIDER: S-EPMC7897324 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Pulse-Chase Proteomics of the App Knockin Mouse Models of Alzheimer's Disease Reveals that Synaptic Dysfunction Originates in Presynaptic Terminals.

Hark Timothy J TJ Rao Nalini R NR Castillon Charlotte C Basta Tamara T Smukowski Samuel S Bao Huan H Upadhyay Arun A Bomba-Warczak Ewa E Nomura Toshihiro T O'Toole Eileen T ET Morgan Garry P GP Ali Laith L Saito Takashi T Guillermier Christelle C Saido Takaomi C TC Steinhauser Matthew L ML Stowell Michael H B MHB Chapman Edwin R ER Contractor Anis A Savas Jeffrey N JN

Cell systems 20201215 2

Compromised protein homeostasis underlies accumulation of plaques and tangles in Alzheimer's disease (AD). To observe protein turnover at early stages of amyloid beta (Aβ) proteotoxicity, we performed pulse-chase proteomics on mouse brains in three genetic models of AD that knock in alleles of amyloid precursor protein (APP) prior to the accumulation of plaques and during disease progression. At initial stages of Aβ accumulation, the turnover of proteins associated with presynaptic terminals is ...[more]

PMID: 33326751

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Dataset Information

Pulse-Chase Proteomics of the App Knockin Mouse Models of Alzheimer's Disease Reveals that Synaptic Dysfunction Originates in Presynaptic Terminals.

Publications

Pulse-Chase Proteomics of the App Knockin Mouse Models of Alzheimer's Disease Reveals that Synaptic Dysfunction Originates in Presynaptic Terminals.

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