Submitted to: Journal of Regulatory Toxicology and Pharmacology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/1/2010
Publication Date: 12/15/2010
Citation: Natarajan, S.S. 2010. Evaluating Natural Variability of Soybean proteins by Proteomic Tools. Journal of Regulatory Toxicology and Pharmacology. 58(3), supplement 1:S26-S29..
Interpretive Summary: Genetically modified (GMO) crops are commonly grown to enhance quality, productivity, and disease resistance. Therefore, it is important to determine changes that occur in the GMO crops as a result of genetic modification to ensure the safety of the crop for consumers. Therefore, we have conducted studies to determine and compare the natural variation of storage proteins, allergen and anti-nutritional proteins between wild and cultivated genotypes. To investigate the natural variation of proteins in soybean, we used a “proteomics” approach, in which seed proteins were separated and then identified, and quantified through the use of mass spectrometry. We observed that the wild soybeans have a larger variation in seed proteins as compared to cultivated soybeans. The results from this study of the natural variation of seed protein expression can be used to determine if the level of proteins accumulated in GMO soybeans exceed the level of respective proteins in non-GMO soybean crops.
Technical Abstract: Soybean is an inexpensive source of protein for humans and animals. Genetic modifications (GMO) to soybean have become inevitable on two fronts, both quality and yield will need to improve to meet increasing global demand. To ensure the safety of the crop for consumers it is important to determine the natural variation in seed protein constituents as well as any unintended changes that may occur in the GMO as a result of genetic modification. Understanding the natural variation of seed proteins in wild and cultivated soybeans that have been used in conventional soybean breeding programs is critical for determining unintended protein expression in GMO soybeans. In recent years, proteomic technologies have been used as an effective analytical tool for examining modifications of protein profiles. We have standardized and applied these technologies to determine and quantify the spectrum of proteins present in soybean seed. We used two-dimensional polyacrylamide gel electrophoresis (2D-PAGE), matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS), and liquid chromatography mass spectrometry (LC-MS) for the separation, quantification, and identification of different classes of soybean seed proteins. We have observed significant variations in different classes of proteins, including storage, allergen and anti-nutritional protein profiles, between non-GMO cultivated and wild soybean varieties. This information is useful for scientists and regulatory agencies to determine whether the unintended expression of proteins found in transgenic soybean is within the range of natural variation.