Polyethylene glycol fractionation improved detection of low-abundant proteins by two-dimensional electrophoresis analysis of plant proteome

A differential polyethylene glycol fractionation protocol was developed for preparation of proteins in 2-DE analysis of plant proteome. The method was proven to detect a total 5077 proteins, among which ca. 80% were undetectable proteins with conventional TCA/acetone precipitation and the reminder exhibited a significant increase in their abundance.