Protein extraction from the stem of Panax ginseng C. A. Meyer: A tissue of lower protein extraction efficiency for proteomic analysis
Ginseng stem, the aerial part of the ginseng is more susceptible to diseases and environmental damages in its long process of growth. Since the molecular mechanism of why ginseng stems are vulnerable remains unclear, the comparison between healthy and pathogen suspicious tissues via proteomics approaches, such as 2-DE, could facilitate the deciphering of the pathogenesis of ginseng and improve ginseng planting industry. A major obstacle for the proteomics study of ginseng stem is the low extraction efficacy of protein due to the properties of its interfering compounds. Here, we tested six different protocols of protein extraction, and identified a protocol that gave us satisfactory yield for 2-DE analysis. The protein extraction was further optimized by chloroform/isoamylol and Tris-saturated phenol extraction that reached the standard of protein purity for 2-DE. Then, using the new extraction protocol, we can efficiently analyze the protein expression patterns of ginseng stem which might provide important information for our understanding of the disease mechanism. Also, our study would lay a foundation for the systematic analysis of the proteomics of ginseng and provide a methodological reference for other similar plant tissues.
Key words: Protein extraction, lower protein extraction efficiency, ginsengstem, two-dimensional electrophoresis.