Global Topology Analysis of Pancreatic Zymogen Granule Membrane Proteins

摘要

The zymogen granule (ZG) is the specialize organelle in pancreatic acinar cells for digestive enzme storage and regulated secretion and is classic model for studying secretory granule function. Our long term goal is to develop a comprehensive molecular architecture for the zymogen granule membrane (ZGM) that would direct new hypotheses for subsequent functional studies. This model will include not only individual components of ZGMs but also their topology, copy number and protein complexes. Our initial proteomics analysis focused on identification of proteins from purified ZGM (Mol Cell Proteomics 5, 306-312, 2006). In the current study, a new global topology analysis of 285 ZGM proteins is described that applies isotope enrichment methods (iTRAQ) to a protease protection analysis.