Cold stress tolerance of Nicotiana tabacum plants transformed with the AtCPK1 gene of Arabidopsis thaliana

Abstract

We studied the effect of an over expression of one of the important calcium sensors, calcium- dependent protein kinase (CDPK), on cold stress tolerance in Nicotiana tabacum L. plants. In this work, we used AtCPK1 gene of Arabidopsis thaliana – one of the most studied isoform of CDPK plant. In addition to the native form of the AtCPK1 gene, its mutant forms, inactive (Na isoform, KJM4 mutation) and regularly active, independent of the presence of calcium ions (Ci isoform, KJM23 mutation), were used. Those gene forms transformed tobacco plants by agrobacterial transformation method. We have shown that the expression of the native form of the gene leads to a significant increase in resistance of the transgene plants both to prolonged exposure of cold and to exposure of cold during germination of seeds as compared to the con- trol plants has been greatly increased. A mutation of KJM23, increases this effect, a mutation of KJM4 completely eliminates this effect.