Biopolymers and cell. 2001; 17 (2): 140 - 146

DNA hypomethylation of sunflower seedlings

E. N. Tishcnenko, L. P. Korzh

The DNA methylation in shoots and roots of etiolated seedlings of sunflower (Helianthus annuus L.) has been investigated. Using the methyl-sensitive enzymes of restriction we showed that CpCpGpG-, CpCpA/TpGpG- and GpApApTpTpC- sites are subjected to dif¬ferential methylation. In particular, these DNA motifs are exten¬sively hypomethylated in shoots, where in contrast to roots, diverse genes are expressed almost 4 times more. The organogenesis in the sunflower callus culture of the shoot apical meristem is also accompanied by the reduction in the level of cytosine enzymatic modification in CpCpGpG- and CpCpA/TpGpG-seguences of DNA. A rote of the DNA enzymatic methylation variability during growth and differentiation of sunflower is under discussion.