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Characterization of Neuronal Lysosome Interactome with Proximity Labeling Proteomics
Published on: June 23, 2022
Niemann-Pick C1 functions in regulating lysosomal amine content
Allyn M Kaufmann1, Jeffrey P Krise
1Department of Pharmaceutical Chemistry, School of Pharmacy, The University of Kansas, Lawrence, Kansas 66047, USA.
The Journal of Biological Chemistry
|July 2, 2008
Summary
Lysosomal amine-containing molecules stimulate Niemann-Pick C1 protein (NPC1) transport, enhancing cargo secretion. NPC1 deficiency increases susceptibility to toxic polyamine metabolites, offering insights into Niemann-Pick disease.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- Mutations in Niemann-Pick C1 (NPC1) disrupt lysosomal transport, causing cargo accumulation.
- Lysosomes contain amine-containing molecules susceptible to ion trapping.
Purpose of the Study:
- To investigate the role of amine-containing molecules in NPC1-mediated lysosomal transport.
- To explore the physiological relevance of this pathway in NPC disease.
Main Methods:
- Cellular assays to measure NPC1-mediated fusion and cargo secretion.
- Analysis of NPC1-deficient cells and fibroblasts.
- Enzyme activity assays for polyamine oxidase.
Main Results:
- Amine-containing molecules enhance NPC1-mediated late endosome/lysosome fusion and cargo secretion.
- NPC1-deficient cells exhibit increased sensitivity to 3-aminopropanal.
- NPC fibroblasts show elevated polyamine oxidase levels.
Conclusions:
- NPC1 plays a novel role in regulating lysosomal transport stimulated by amine-containing molecules.
- This pathway is crucial for cellular defense against toxic metabolites.
- Findings may elucidate Niemann-Pick disease progression.
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