Proteome Changes in Maize Embryo(Zea mays L)Induced by Ion Beam Implantation Treatment

Low energy ion beam implantation was applied to the maize (Zea mays L) embryoproteome using two-dimensional gel electrophoresis. Protein profile analysis detected more than1100 protein spots, 72 of which were determined to be expressed differently in the treated andcontrol (not exposed to ion beam implantation) embryos. Of the 72 protein spots, 53 were up-regulated in the control and 19 were more abundantly expressed in the ion beam-treated embryos.The spots of up- or down-regulated proteins were identified by matrix assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS). Among the identified proteins,11 were up-regulated in the treated embryos. Four of these up-regulated proteins were antioxidantmolecules, three were related to stress response, two to sugar metabolism and two were associatedwith heat shock response. Of the five proteins up-regulated in the control embryos, three werefunctionally related to carbohydrate metabolism; the functions of the remaining two proteins wereunknown. The data collected during this study indicate that treatment of maize embryos withlow energy ion beam implantation induces changes in stress tolerance enzymes/proteins, possiblyas a result of alterations in metabolism.