CRYOPRESERVATION DOES NOT AFFECT THE EXPRESSION OF A FOREIGN SAM GENEIN TRANSGENIC PAPAVER-SOMNIFERUM CELLS

Transgenic cell lines of Papaver somniferum have been obtained via Agr obacterium tumefaciens. Papaver somniferum is known to be genetically unstable in in vitro culture conditions. Cryopreservation at ultra-low temperature is an appropriate strategy for long-term preservation of germplasm. We have studied the effects of osmotic stress due to cryopr otectants during pretreatment and of storage at -196 degrees C on the stability and the expression of the foreign sam1 gene from Arabidopsis thaliana. We established that the integrity, transcription of the tra nsgene and enzymatic activity of its product were not affected by cryo preservation in liquid nitrogen.