ER-associated degradation regulates Alzheimer's amyloid pathology and memory function by modulating γ-secretase activity

作者：Zhu, Bing; Jiang, Lulin; Huang, Timothy; Zhao, Yingjun; Liu, Tongfei; Zhong, Yongwang; Li, Xiaoguang; Campos, Alexandre; Pomeroy, Kenneth; Masliah, Eliezer; Zhang, Dongxian; Xu, Huaxi^*

来源：Nature Communications, 2017, 8(1): 1472.

DOI：10.1038/s41467-017-01799-4

• RETICULUM-ASSOCIATED DEGRADATION
• UBIQUITIN PROTEASOME SYSTEM
• BETA-PEPTIDE PRODUCTION
• NEURODEGENERATIVE DISEASES
• ENDOPLASMIC-RETICULUM
• PRESENILIN/GAMMA-SECRETASE
• SYNAPTIC DYSFUNCTION
• COGNITIVE DEFICITS
• LIGASE
• NICASTRIN

Endoplasmic-reticulum-associated degradation (ERAD) is an important protein quality control system which maintains protein homeostasis. Constituents of the ERAD complex and its role in neurodegeneration are not yet fully understood. Here, using proteomic and FRET analyses, we demonstrate that the ER protein membralin is an ERAD component, which mediates degradation of ER luminal and membrane substrates. Interestingly, we identify nicastrin, a key component of the gamma-secretase complex, as a membralin binding protein and membralin-associated ERAD substrate. We demonstrate a reduction of membralin mRNA and protein levels in Alzheimer's disease (AD) brain, the latter of which inversely correlates with nicastrin abundance. Furthermore, membralin deficiency enhances gamma-secretase activity and neuronal degeneration. In a mouse AD model, downregulating membralin results in beta-amyloid pathology, neuronal death, and exacerbates synaptic/memory deficits. Our results identify membralin as an ERAD component and demonstrate a critical role for ERAD in AD pathogenesis.

• 出版日期2017-11-13
• 单位厦门大学