[Establishment of protein expression profile of human normal colonic epithelia].

Objective: To establish a protein expression profile of human normal colonic epithelia.

Methods: Two-dimensional gel electrophoresis (2-DE) was applied to separate the total proteins of 20 human normal colonic epithelial tissues. The expression proteins in the human normal colonic epithelia were identified by both matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) and electrospray ionization tandem mass spectrometry (ESI-Q-TOF), and the biological function and subcellular locations of the identified proteins were analyzed by bioinformatics.

Results: A 2-DE reference map of human normal colonic epithelium was established. On the 2-DE map, 1020+/-50 protein spots were detected, 204 protein spots representing 162 non-redundant proteins were identified, and 37 proteins had posttranslational modification. The identified proteins were categorized into several protein groups according to their functions or subcellular locations, whose data were available at our website (http://www.xyproteomics.org).

Conclusion: A protein expression profile of human normal colonic epithelia is established for the first time, which provides useful information for investigating the physiological functions and pathologic process of colonic epithelia.