The overexpression of an alternative oxidase gene contributes to growth and development of arabidopsis plants under uv radiation impact

To study the role of alternative respiratory pathway in plant growth reactions to chronic ultraviolet (UV) radiation, transformed lines of Arabidopsis thaliana were used: AOX1a overexpressors (XX-2), AOX1a anti-sense plants (AS-12). Mutants were compared with the untransformed wild type Columbia (Col-0). Three-week-old Arabidopsis plants were exposed to supplemental UV radiation. The calculated daily doses of UV-A and UV-B were 38 и 0.5 kJ/м 2 respectively. After 10 days of UV-treatment leaf area in the AOX-overexpressing line decreased to a lesser extent compared to the wild type Col-0 and the line AS-12. As a result of the leaf area decrease the plants of the mutant line XX- 2 had a larger seed yield per plant than those of the anti-sense line and the wild type. Since in these transformed plants, AOX protein level affects ROS formation when the cytochrome pathway is restricted, a higher AOX engagement may lead to less ROS production, and hence may maintain more optimal conditions for growth.