OBJECTIVETo establish an effective separation system of 2-DE for the proteome of caudal gland, and provide foundation for revealing the mechanisms of histological development and pharmacological activities.

METHODThe total proteins of caudal gland were extracted by TCA/acetone precipitation, phenol extraction/methanol-ammonium acetate precipitation and trizol-base method respectively and separated by immobilized pH gradient (IPG) strips prior to SDS-PAGE. Loading protein sample size and isoelectric focusing conditions were optimized. The gels were stained with Coomassie brilliant blue, scanned and then analyzed using PDQuest 8.0 analysis software.

RESULTThe total proteins of caudal gland extracted by trizol-base method were the highest quality and could meet the needs of 2-DE. With 300 microg of proteins loaded on 7 cm pH 3-10 IPG strip followed by isoelectric focusing program II ,a satisfying 2-DE profiles were obtained. The total number of disticted protein spots was 209 with the optimized system.

CONCLUSIONA well-resolved 2-DE patterns of caudal gland were obtained by this optimized system. This method could be applied to prepare other similar tissue sample and 2-DE studies.