MALDI imaging and in situ identification of integral membrane proteins from rat brain tissue sections.

Nicklay JJ, Harris GA, Schey KL, Caprioli RM
Anal Chem. 2013 85 (15): 7191-6

PMID: 23829295 · PMCID: PMC3782084 · DOI:10.1021/ac400902h

Transmembrane proteins are greatly underrepresented in data generated by imaging mass spectrometry (IMS) because of analytical challenges related to their size and solubility. Here, we present the first example of MALDI IMS of two highly modified multitransmembrane domain proteins, myelin proteolipid protein (PLP, 30 kDa) and DM-20 (26 kDa), from various regions of rat brain, namely, the cerebrum, cerebellum, and medulla. We utilize a novel tissue pretreatment aimed at transmembrane protein enrichment to show the in situ distribution of fatty acylation of these proteins, particularly of post-translational palmitoylation. Additionally, we demonstrate the utility of protease-encapsulated hydrogels for spatially localized on-tissue protein digestion and peptide extraction for subsequent direct coupling to LC-MS/MS for protein identification.

MeSH Terms (8)

Animals Brain Molecular Imaging Myelin Proteolipid Protein Rats Rats, Sprague-Dawley Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization Trypsin

Connections (3)

This publication is referenced by other Labnodes entities: