MOLECULAR NETWORK CONTROLLING THE OVULE DEVELOPMENT IN ARABIDOPSIS THALIANA

Ovules are the essential organ for plant reproduction. Megasporogenesis, megagametogenesis, fertilization and embryogenesis take place within the ovule. In the ovule both sporophytic and gametophytic generation coexist. The analyses of this developmental process provides an excellent tool to understand the molecular mechanism involved in controlling the basic processes like primordia initiation, specification, cell division, expansion and differentiation. This system allows the study of basic developmental process as well as the evolutionary prospect in the same context. In my thesis I have used Arabidopsis thaliana as a model system.The aim of this project is to study the genetic and hormone network controlling ovule primordia formation. Reduction in number of ovule primordia was already described in the ant mutant (Baker et al., 1996). cuc1 and cuc2 single mutant display similar number of ovule primordia like wild type. Double mutant cuc1cuc2 shows defect in shoot apical meristem formation, two cotyledons fused along their margin to form a cup shaped structure (Aida et al., 1997). Normally it is difficult to get the double mutant plants from the fused cotyledon. Adventitious shoots regenerated from mutant calli form the double mutant flowers, which also display the reduction of number of ovule primordia (Ishida et al., 2000). The goal of this work was to investigate the interaction among ANT, CUC1, CUC2 genes to determine ovule primordia formation.