Erlin-2 is associated with active γ-secretase in brain and affects amyloid β-peptide production.

Teranishi Y, Hur JY, Gu GJ, Kihara T, Ishikawa T, Nishimura T, Winblad B, Behbahani H, Kamali-Moghaddam M, Frykman S, Tjernberg LO

Biochem. Biophys. Res. Commun. 424 (3) 476-481 [2012-08-03; online 2012-07-10]

The transmembrane protease complex γ-secretase is responsible for the generation of the neurotoxic amyloid β-peptide (Aβ) from its precursor (APP). Aβ has a causative role in Alzheimer disease, and thus, γ-secretase is a therapeutic target. However, since there are more than 70 γ-secretase substrates besides APP, selective inhibition of APP processing is required. Recent data indicates the existence of several γ-secretase associated proteins (GSAPs) that affect the selection and processing of substrates. Here, we use a γ-secretase inhibitor for affinity purification of γ-secretase and associated proteins from microsomes and detergent resistant membranes (DRMs) prepared from rat or human brain. By tandem mass spectrometry we identified a novel brain GSAP; erlin-2. This protein was recently reported to reside in DRMs in the ER. A proximity ligation assay, as well as co-immunoprecipitation, confirmed the association of erlin-2 with γ-secretase. We found that a higher proportion of erlin-2 was associated with γ-secretase in DRMs than in soluble membranes. siRNA experiments indicated that reduced levels of erlin-2 resulted in a decreased Aβ production, whereas the effect on Notch processing was limited. In summary, we have found a novel brain GSAP, erlin-2, that resides in DRMs and affects Aβ production.

Affinity Proteomics Uppsala [Technology development]

PLA and Single Cell Proteomics

PubMed 22771797

DOI 10.1016/j.bbrc.2012.06.137

Crossref 10.1016/j.bbrc.2012.06.137

pii: S0006-291X(12)01239-9