Abstract
The lysosomal integral membrane protein type-2 (LIMP-2) plays a pivotal role in the delivery of β-glucocerebrosidase (GC) to lysosomes. Mutations in GC result in Gaucher's disease (GD) and are the major genetic risk factor for the development of Parkinson's disease (PD). Variants in the LIMP-2 gene cause action myoclonus-renal failure syndrome and also have been linked to PD. Given the importance of GC and LIMP-2 in disease pathogenesis, we studied their interaction sites in more detail. Our previous data demonstrated that the crystal structure of LIMP-2 displays a hydrophobic three-helix bundle composed of helices 4, 5, and 7, of which helix 5 and 7 are important for ligand binding. Here, we identified a similar helical motif in GC through surface potential analysis. Coimmunoprecipitation and immunofluorescence studies revealed a triple-helical interface region within GC as critical for LIMP-2 binding and lysosomal transport. Based on these findings, we generated a LIMP-2 helix 5-derived peptide that precipitated and activated recombinant wild-type and GD-associated N370S mutant GC in vitro. The helix 5 peptide fused to a cellpenetrating peptide also activated endogenous lysosomal GC and reduced α-synuclein levels, suggesting that LIMP-2-derived peptides can be used to activate endogenous as well as recombinant wild-type or mutant GC efficiently. Our data also provide a structural model of the LIMP-2/GC complex that will facilitate the development of GC chaperones and activators as potential therapeutics for GD, PD, and related synucleinopathies.
Original language | English (US) |
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Pages (from-to) | 3791-3796 |
Number of pages | 6 |
Journal | Proceedings of the National Academy of Sciences of the United States of America |
Volume | 113 |
Issue number | 14 |
DOIs | |
State | Published - Apr 5 2016 |
Funding
We thank Ellen Sidransky and Pamela McLean for the β-glucocerebrosidase (GC)-deficient mouse embryonic fibroblasts and H4 cells, respectively, and Johannes Aerts (Leiden University) for the GC antibody and for critically reading the manuscript. This work was supported by a Böhringer Ingelheim Fonds Fellowship (to F.Z.), a Deutsche Forschungsgemeinschaft (DFG) Heisenberg fellowship (to M.S.), and DFG Grants GRK1459 (to M.S. and J.B.), R01NS076054 (to D.K.), and R01NS092823 (to J.R.M.).
Keywords
- GC activators
- Gaucher's disease
- LIMP-2
- Parkinson's disease
- β-glucocerebrosidase
ASJC Scopus subject areas
- General