Flax Genomic Elements Active in Somatic Genomic Reorganization

The flax genome can be modified somatically depending on the growth environment. This property appears to be genetically controlled with the extent of variability dependent on the genotype of the line under study. One element, LIS-1, has a novel genesis in that it arises de novo in particular lines under specific growth conditions. The appearance and persistence of this element is dependent on both the genotype and growth conditions of the variety under study. In flax, the appearance of LIS-I in subsequent generations has been associated with the loss of the ability to respond to the original growth conditions so it has not been possible to determine the reversibility of this process. Two questions arise from these observations. Firstly, is LIS-1 an element that is unique to flax or can it "recognized" by other plant species. Secondly is LIS-1 persistence in flax also dependent on the subsequent growth conditions if it is present in a variety that can still undergo genomic reorganization. These questions have been addressed by developing transgenic lines of flax and Arabidopsis that contain LIS-1. In Arabidopsis, LIS-1 is unstable and the extent of the instability appears to be genotype dependent. In flax, a responsive line has been transformed with an intact LIS-1 element and its stability in the T1 generation determined. LIS-1 can be lost in these transgenic plants in the absence of the inducing environment, which is consistent with the presence of LIS-1 being positively selected for in inducing