SPOT: spatial proteomics through on-site tissue-protein-labeling

Area of Science:

• Proteomics
• Biotechnology
• Molecular Biology

Background:

• Spatial proteomics aims to map protein organization within tissues and subcellular compartments.
• Current methods face challenges in accurately capturing in-situ protein spatial distribution.
• The Spatial Proteomics through On-site Tissue-protein-labeling (SPOT) approach is introduced to address these limitations.

Purpose of the Study:

• To develop and validate an innovative technique for spatially-resolved proteomics.
• To assess the efficacy of direct TMT labeling on various tissue types and preparations.
• To demonstrate the application of SPOT in analyzing complex biological samples like mouse brains and human prostate cancer.

Main Methods:

• Direct labeling of tissue proteins in situ on slides using TMT tags.
• Quantitative mass spectrometry for proteomic profiling.
• Evaluation of SPOT on diverse mouse brain tissue slides (frozen, FFPE, stained) and human prostate cancer tissues/TMAs.

Main Results:

• Successful direct TMT labeling of proteins across various mouse brain tissue preparations.
• SPOT effectively distinguished specific mouse brain regions based on quantitative proteomic data.
• Distinct proteomic profiles were identified in human prostate cancer tissues with varying Gleason scores using SPOT.

Conclusions:

• SPOT is a robust and versatile technique for comprehensive, spatially-resolved proteomic profiling.
• The method is applicable to diverse tissue types, including frozen and FFPE samples.
• SPOT advances the understanding of intricate molecular landscapes in native tissue environments.