- Manxi Yang Purdue University West Lafayette ,
- Hang Hu Purdue University West Lafayette ,
- Pei Su Northwestern University & Purdue University West Lafayette ,
- Paul M. Thomas Northwestern University ,
- Jeannie M. Camarillo Northwestern University ,
- Joseph B. Greer Northwestern University ,
- Bryan P. Early Northwestern University ,
- Ryan T. Fellers Northwestern University ,
- Neil L. Kelleher Northwestern University ,
- Julia Laskin Purdue University West Lafayette
Unraveling the complexity of biological systems relies on the development of new approaches for spatially resolved proteoform-specific analysis of the proteome. Herein, we employ nanospray desorption electrospray ionization mass spectrometry imaging (nano-DESI MSI) for the proteoform-selective imaging of biological tissues. Nano-DESI generates multiply charged protein ions, which is advantageous for their structural characterization using tandem mass spectrometry (MS/MS) directly on the tissue. Proof-of-concept experiments demonstrate that nano-DESI MSI combined with on-tissue top-down proteomics is ideally suited for the proteoform-selective imaging of tissue sections. Using rat brain tissue as a model system, we provide the first evidence of differential proteoform expression in different regions of the brain.
The manuscript was polished and proteoform assignments were updated.