4Pattern of DNA cytosine methylation in Aeluropus littoralis during temperature stress

DNA methylation as an epigenetic mediator plays the important role in spatial and temporal gene regulationand ensures the stability and the plasticity of organism. In this investigation, methylation sensitiveamplification polymorphism (MSAP) were assessed in CCGG sites on a halophytic plant, Aeluropus littoralisin response to different temperature stresses including freezing, low and high temperatures. A combination of13 primers were able to produce 500 bands, of which 74%, 20.8% and 5.2% were of type I (non methylatedfragments), type II (CpG methylated fragments) and type III (CpCpG methylated fragments), respectively.Among these bands, 130 bands were methylated fragments with the highest occurrence of methylation at CpGinternal cytosine. The results showed that up to 2% of all methylated bands were polymorphic, whichbelonged to types II and III. Highest levels of methylation alternations were detected under high and freezingtemperatures. The results suggest that apart from cis regulatory logic plant response to the environmentaltemperatures may be regulated by methylation of CCGG sites of stress-related loci.