Abstract
Abstract Water deficit is a serious environmental factor limiting the growth and productivity of plants and agricultural crops worldwide. A number of these plants and crops own the ability to survive drought by altering the level of gene expression. Using Arabidopsis in studying gene function and regulation is of crucial importance to plant biotechnology. Our objective was to study the gene expression of C-repeat- Binding Factor 4/ Dehydration Responsive Element-binding Protein 1D (CBF4/DREB1D) (At5g51990) under drought using cbf4 mutant line (SALK_039486). Two separate experiments were performed. In the first one, plants of homozygous and wild type lines were grown on the same soil, and in the second one; plants of the two lines in parallel with Columbia 8 were grown on separate pots. The molecular analysis showed that the insert is located 52 bases downstream the gene and the mutant were segregated out in a different manner from the mendelian bases. The gene expression of CBF4 was greatly reduced in the mutant comparing to wild type but Plant survival showed no significant differences between the different genotypes in both experiments. The mRNA detection indicates the role of CBF4 in drought stress response in Arabidopsis as the mutant showed gene down-regulation but this level was not low enough to affect plant survival.