Changes in Protein Expression Profiles between a Low Phytic Acid Rice (Oryza sativa L. Ssp japonica) Line and Its Parental Line: A Proteomic and Bioinformatic Approach

The seed proteome of a low phytic acid (lpa) rice line (Os-lpa-XS110-1), developed as a novel food source, was compared to that of its parental line, Xiushui 110 (XS-110). Analysis by surfaced enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF MS) and two-dimensional gel electrophoresis (2-DE) allowed the detection of a potential low molecular weight biomarker and identification of 23 differentially expressed proteins that include stress-related proteins, storage proteins, and potential allergens. Bioinformatic analyses revealed that triose phosphate isomerase (TPI) and fructose bisphosphatealdolase (FBA), two major differentially expressed proteins, are involved in myo-inositol metabolism. Accumulation of globulin was also significantly decreased in the lpa line. This study demonstrates the potential of proteomic and bioinformatic profiling techniques for safety assessment of novel foods. Furthermore, these techniques provide powerful tools for studying functional genomics due to the possibility of identifying genes related to the mutated traits.