Abstract
Flooding injury is one of the major constraints for cultivation of soybean. A proteomic approach was used for clarifying mechanisms of the flooding injury. Two-day-old seedlings were flooded with water for 12 h, and the roots and hypocotyls were used for 2D-DIGE analysis using CyDye fluorescence labeling with the comparative analysis between untreated and flooding treated samples. Out of detected 555 protein spots, significantly changed 17 protein spots were identified by nanoLC-MS/MS. The identification revealed that flooding caused increase of proteins involved in glycolysis and glycolysis related detoxification and decrease of proteins involved in phenylpropanoid metabolism. On the other hand, phosphorylated proteins were analyzed by Pro-Q diamond staining following 2D-PAGE separation. Out of detected 121 phosphoprotein spots, the phosphorylation levels of 16 protein spots were significantly changed and which contain proteins involved in protein translation. These results suggest that induction of glycolysis and glycolysis related detoxification are primary responses and protein phosphorylation is involved in regulation of protein translation in the early response of flooding.
