ENHANCEMENT OF THE TOLERANCE OF ARABIDOPSIS TO HIGH-TEMPERATURES BY GENETIC-ENGINEERING OF THE SYNTHESIS OF GLYCINEBETAINE

Arabidopsis thaliana was transformed with the codA gene for choline ox idase from Arthrobacter globiformis under control of the 35S RNA promo ter of cauliflower mosaic virus. As a result, high levels of glycinebe taine accumulated in the seeds of transformed plants. Transformation w ith the codA gene significantly enhanced the tolerance to high tempera tures during the imbibition and germination of seeds, as well as durin g growth of young seedlings. The extent of enhancement of the toleranc e to high temperature was correlated with levers of choline oxidase ex pressed and of glycinebetine accumulated in the transformed plants. Th e induction of homologues of heat shock protein 70 at high temperature was less conspicuous in the transformed plants than in the wild-type plants, suggesting that the transformation alleviated the high-tempera ture stress.