The proteins of cotton(Gossypium hirsutum) were extracted by TCA-acetone method and the technique of two-dimensional electrophoresis in cotton proteomics was improved.Some satisfied pictures were obtained through optimizing many key procedures,such as sample preparation,sample dissolution,IPG stripe,IEF electrophoresis,SDS-PAGE.Then proteins from cold treated cotton cotyledon for 12 hours were extracted and separated by 2-DE.A large quantity of protein spots appeared in pictures.PDQuest software was used to...