On the role of vitamin E in Arabidopsis thaliana seedlings growing at low light intensity

摘要

Seedlings of Arabidopsis thaliana wild type (WT) and two mutants: 1. with impaired synthesis of alpha-and gamma-tocopherols (vte1) and 2. accumulating of gamma-tocopherol instead of alpha-tocopherol (vte4) were grown in the presence of 100 mM NaCl or 10 muM methyl viologen under low light. On the basis of oxidative stress parameters (SOD, catalase activities) and maximal PSII quantum efficiency (F_v/F_m) at predawn and afternoon measured on WT, vte1 and vte4 plants we state that gamma-tocopherol plays an important protective role against photoinhibition during the early stage of plant development. We suggest that impairment of tocopherol synthesis might cause the alteration in the function of photosynthetic apparatus. Salinity stress at low light intensity can exert positive effect on growth and metabolism of A. thaliana seedlings. Tocopherols at low light perform other than only antioxidant function.