The roots of Platycodon grandiflorum species either dried or fresh, are used as an ingredient in salads and traditional cuisine in Korea. To interpret the root proteins, a systematical and targeting analysis were carried out from diploid and tetraploid roots. Two dimensional gels stained with CBB, a total of 39 differential expressed proteins were identified from the diploid root under in vivo condition using image analysis by Progenesis Same Spot software. Out of total differential expressed spots, 39 differential expressed protein spots (≥ 1.5-fold) were analyzed using LTQ-FTICR mass spectrometry. Except two proteins, the rest of the identified proteins were confirmed as down-regulated such as Isocitrate dehydrogenase, Proteasome subunit alpha type-2-B. However, the most of the identified proteins from the explants were mainly associated with the oxidoreductase activity, nucleic acid binding, transferase activity and catalytic activity. The exclusive protein profile may provide insight clues for better understanding the characteristics of proteins and metabolic activity in various explants of the economically important medicinal plant Platycodon grandiflorum.

The roots of Platycodon grandiflorum are massively used in traditional herbal medicine as a remedy for pulmonary disease and respiratory disorders. However, in spite of its potential medicinal significance, the molecular mechanism of its roots is still unknown. In the present study, high throughput proteome approach was conducted to profile proteins from 3, 4 and 5 months aged diploid and tetraploid roots of Platycodon grandiflorum. Two dimensional gels stained with CBB, a total of 68 differential expressed proteins were identified from diploid root out of 767 protein spots using image analysis by Progenesis SameSpot software. Out of total differential expressed spots, 29 differential expressed protein spots (≥ 2-fold) were analyzed using LTQ-FTICR MS whereas a total of 24 protein spots were up regulated and 5 protein spots were down-regulated. On the contrary, in the case of tetraploid root, a total of 86 differential expressed proteins were identified from tetraploid root out of 1033 protein spots of which a total of 39 differential expressed protein spots (≥ 2-fold) were analyzed using LTQ-FTICR MS whereas a total of 21 protein spots were up regulated and a total of 18 protein spots were down-regulated. It was revealed that the identified proteins from the explants were mainly associated with the nucleotide binding, oxidoreductase activity, transferase activity. In that way, the exclusive protein profile may provide insight clues for better understanding the characteristics of proteins and metabolic activity in various explants of the economically important medicinal plant Platycodon grandiflorum.