Two-dimensional electrophoresis (2-DE) was executed to separate the seed storage proteins from the buckwheat. The proteins extracted from the whole seed proteins were better separated and observed in the use of lysis buffer. Using this method, the highly reproducible isoelectric focusing (IEF) can be obtained from polyacrylamide gels, and IEF from the polyacrylamide gel at all the possible pH range (5.0-8.0) was more easily separated than IPG (immobilized pH gradient) gels. The polyacrylamide gels in the first dimension in 2-DE was used to separate and identify a number of whole seed proteins in the proteome analysis. In this new apparatus using 2-DE, 27cm in length of plate coated with polyacrylamide gel was used and the experiment was further investigated under the various conditions.

Chilling stress affects growth and yield of warm-climate crops such as soybean (Glycine max L.) that is susceptible to low temperature (10-18℃). A comparative proteomic approach was employed to explore the mechanisms underlying soybean response to chilling stress. Soybean seedlings were germinated for 3-4 days and exposed to low temperature (10℃) for 3 days, and the proteins were extracted from seedling leaves. Protein separation by SDS-PAGE followed by liquid chromatography electro-spray ionization tandem mass spectrometry (LC-ESI MS/MS) was effective approach to identify proteins, based on the number of peptides reliably identified. A total of 77 proteins out of 704 proteins were identified in the presence of chilling stress. Most proteins identified had functions related to cell signaling, metabolism, energy and transport, protein biosynthesis and degradation, cytoskeleton, and were involved in regulating reactions and defending against stress. It is therefore likely that the response of soybean plant’s proteome to chilling stress is complex, and that the identification proteins may play an important role in regulating adaptation activities following challenge to chilling stress to facilitate cellular homeostasis. Furthermore, our result suggest that new ways of engineering stress-tolerant plants responding climate change by providing outline for agriculturally important chilling stress.