Functional conservation of the IDA signalling pathway in Angiosperms

Plants are provided with mechanisms whereby leaves, flowers, seeds and fruits are dethatched from the plant once they have served their purpose. Flowers will detach after fertilization and seeds and fruits when mature. These detachments are controlled by cell separation processes, where the cell wall between the cells that are going to separate are broken down. Before the separation takes place a cellular signaling pathway is initiated. In the model plant thale cress, when the plant is ready to discard a floral organ, a small protein called IDA is produced and secreted from the cells in the area where the separation is going to happen. On the surface of the cells IDA binds to receptors, which in turn get activated and induce cellular signals leading to a breakdown of the cell wall surrounding the cell. In this thesis we have investigated whether the function of IDA is conserved in other plant species as well as IDA's involvement during other cell separation events such as seed abscission and lateral root emergence. We have shown that the IDA gene is present in all flowering plants, and is active during cell separation in both mono- and eudicot species. We have further investigated the function of IDA in the mustard family with includes agricultural important plants such as cruciferous vegetables, cabbages and mustard plants. Knowledge of the function of IDA in thale cress and other plant species may aid in further studies of important plant for food production.