Profile-Based Proteomic Investigation of Unintended Effects on Transgenic and Gamma Radiation Induced Mutant Soybean Plants

Abstract

GM risk assessments are crucial for determination and prevention of potential adverse effects through early detection and proper evaluation of intended and potential unintended changes in molecular breeding. In this context, the concept of 'substantial equivalence' has been suggested for the safety tests of GM products for many years. This study evaluated differences between four types of Glycine max crops; transgenic soybean, its non-transgenic counterpart, gamma induced soybean mutant and its parental line, at proteomic level in context of substantial equivalence. The results revealed the ratio of differentially expressed protein spots to total protein spots in mutants compared to their parental line was 50.7%. This ratio was 41.2% in transgenic plants compared to their counterparts. Scatter plot analysis presented those mutant plants showed a wider spread than transgenic plants in terms of distribution of proteins. It was determined that up-regulated proteins in mutant plants have various biological roles in processes such as development, stress response, photorespiration and ribosomal subunit assembly. In transgenic plants, upregulated proteins were shown to have diverse biological roles in processes such as ribosomal subunit assembly, electron transport, amino acid and nucleic acid metabolism and cell wall biogenesis. Although debate on the potential unintended effects focuses on GM organisms, our results point out that the plants that gained new characteristics by various breeding methods should be characterized in all aspects case-by-case.