In Situ Imaging of N‐Glycans by MALDI Imaging Mass Spectrometry of Fresh or Formalin‐Fixed Paraffin‐Embedded Tissue

• DOI: 10.1002/cpps.68
• Publication Date: 2018-08-07T05:17:43Z
• Authors: Richard R. Drake; Thomas W. Powers; Kim Norris‐Caneda; Anand S. Mehta; Peggi M. Angel
• Keywords: PNGase F; Endoglycosidase; Exoglycosidase; Oligosaccharide; Mass spectrometry imaging; N-linked glycosylation

Abstract Glycosylation of cell surface, secreted, and circulating proteins is one the most common types post‐translational modification. These modifications occur commonly as three major classes: N‐linked glycosylation on asparagine residues, O‐linked serine or threonine glycosaminoglycan oligosaccharide polymers serine. Specifically, for glycans, an endoglycosidase enzyme, peptide N‐glycosidase F (PNGase F), cleaves attached oligosaccharides between first sugar. A method to analyze released N‐glycans map them specific locations within a tissue presented here. The PNGase applied by solvent sprayer molecular layer frozen formalin‐fixed tissues all in given region are detected using matrix‐assisted laser desorption/ionization (MALDI) imaging mass spectrometry (MALDI‐IMS). Using described MALDI‐IMS protocol, at least 40 more individual can be mapped histopathology extracted further structural analysis approaches. © 2018 John Wiley & Sons, Inc.