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Updated: Jul 4, 2026
10:11
Glycopeptide Capture for Cell Surface Proteomics
Published on: May 9, 2014
The mannose 6-phosphate glycoprotein proteome
David E Sleat1, Maria Cecilia Della Valle, Haiyan Zheng
1Center for Advanced Biotechnology and Medicine and Department of Pharmacology, University of Medicine and Dentistry of New Jersey, Piscataway, New Jersey 08854, USA. sleat@cabm.rutgers.edu
Journal of Proteome Research
|May 30, 2008
Summary
Researchers identified 136 new candidate lysosomal proteins by analyzing mannose 6-phosphate (Man6-P) glycoproteins across 17 rat tissues. This global glycoproteome analysis advances lysosome discovery and understanding of protein distribution.
Area of Science:
- Cell Biology
- Biochemistry
- Proteomics
Background:
- Lysosomal proteins are synthesized with mannose 6-phosphate (Man6-P) tags.
- Previous studies identified ~60 known lysosomal proteins via Man6-P affinity purification.
- Identifying novel lysosomal proteins among Man6-P glycoproteins is challenging.
Purpose of the Study:
- To perform a global analysis of the mammalian Man6-P glycoproteome.
- To discover and validate novel lysosomal protein candidates.
- To understand the distribution of Man6-P glycoproteins.
Main Methods:
- Purification of Man6-P glycoproteins from 17 rat tissues.
- Affinity chromatography using Man6-P.
- Quantitative mass spectrometry to compare specific vs. non-specific eluates.
- Biostatistical analysis for candidate validation.
Main Results:
- Identified 60 known lysosomal proteins containing Man6-P.
- Discovered 136 additional proteins specifically purified via Man6-P affinity.
- These 136 proteins are potential novel lysosomal candidates.
- Provided insights into Man6-P glycoprotein distribution.
Conclusions:
- This study presents a validated list of candidate lysosomal proteins.
- The approach enhances the discovery of proteins involved in lysosomal function.
- Findings contribute to understanding lysosome composition and biogenesis.
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