Ferritin light chain interacts with PEN-2 and affects γ-secretase activity.

TitleFerritin light chain interacts with PEN-2 and affects γ-secretase activity.
Publication TypeJournal Article
Year of Publication2013
AuthorsLi X, Liu Y, Zheng Q, Yao G, Cheng P, Bu G, Xu H, Zhang Y-W
JournalNeuroscience letters
Volume548
Pagination90-4
Date Published2013 Aug 26
Abstract

Alzheimer's disease (AD) is primarily caused by overproduction/deposition of β-amyloid (Aβ) in the brain. Dysregulation of iron in the brain also contributes to AD. Although iron affects β-amyloid precursor protein (APP) expression and Aβ deposition, detailed role of iron in AD requires further elucidation. Aβ is produced by sequential proteolytic cleavages of APP by β-secretase and γ-secretase. The γ-secretase complex comprises presenilins (PS1 or PS2), nicastrin, APH-1, and PEN-2. Herein, we find that PEN-2 can interact with ferritin light chain (FTL), an important component of the iron storage protein ferritin. In addition, we show that overexpression of FTL increases the protein levels of PEN-2 and PS1 amino-terminal fragment (NTF) and promotes γ-secretase activity for more production of Aβ and notch intracellular domain (NICD). Furthermore, iron treatments increase the levels of FTL, PEN-2 and PS1 NTF and promote γ-secretase-mediated NICD production. Moreover, downregulation of FTL decreases the levels of PEN-2 and PS1 NTF. Together, our results suggest that iron can increase γ-secretase activity through promoting the level of FTL that interacts with and stabilizes PEN-2, providing a new molecular link between iron, PEN-2/γ-secretase and Aβ generation in AD.

DOI10.3978/j.issn.2225-319X.2013.06.03
Alternate JournalNeurosci. Lett.