Changes in Protein Pattern during Stress-induction of Carrot (Daucus carota L.) Somatic Embryogenesis

Abstract

To clarify the molecular biological aspects occurring during the induction of somatic embryogenesis, the stress-induced changes in protein pattern and the proteins associated with somatic embryogenesis induced by stress in carrot (Daucus carota L.) were investigated. In two dimensional polyacrylamide gel electrophoresis (2D-PAGE), 6 spots with molecular weight of 63-65 kilo Dalton (KDa) showing pI ranging from 6.0-6.5, and 2 spots of molecular weight 45KDa with a pI of 5.0 were detected in the extracts of apical tip segments treated with cadmium chloride, sucrose and sodium chloride. Three spots out of the 6 spots of 63-65KDa molecular weight and the two 45KDa spots were also detected in the extracts of 2, 4-dichlorophenoxy acetic acid (2, 4-D)-induced embryogenic cells, but not in those of non-embryogenic cells. Furthermore, these 5 spots were also detected in the extracts of hypocotyl segments cultured with 2, 4-D for more than 4 weeks. Judging from the relationship between accumulation of these proteins and acquisition of embryogenic competence, these proteins may be related to acquisition and/or maintenance of embryogenic competence.