EMBRYOGENESIS-RELATED PROTEIN-SYNTHESIS AND ACCUMULATION DURING EARLY ACQUISITION OF SOMATIC EMBRYOGENESIS COMPETENCE IN CICHORIUM

Somatic embryogenesis in Cichorium intybus was achieved from leaves. In the presence of glycerol in a half-strength Murashige and Skoog medium, mesophyll cells were induced to undergo somatic embryogenesis. The first division occurred 3 h after transfer of the synchronised embryogenic cells to a medium lacking glycerol (expression medium). Protein accumulation and synthesis during early embryogenesis was analysed using two-dimensional PAGE. As demonstrated by silver-staining and autoradiography of [S-35]methionine-labelled polypeptides, most of the changes in protein pattern occurred by the third day of induction, before the first cellular division and well before any overt signs of morphological changes. At least 15 embryogenesis-related proteins were detected during induction of cells for morphogenic competence. This suggests that acquisition of the embryogenic competence which involves reprogramming of differentiated cells occurred early during the induction step in Cichorium leaves. The role of the embryogenesis-related proteins in the embryogenesis process is still unknown but they may play different roles in the acquisition of the embryogenic competence.