Analysis of DNA Methylation Status of the OsSOS1 Gene under Salt Stress in Rice
OsSOS1 is a Na+/H+ transporter presented on cellular membranes which plays a crucial
role in salt response in plant through SOS pathway. DNA methylation is an inherited and
reversible epigenetic modification which affects directly on the regulation of gene expression, and
therefore might effect on salt tolerance in plant. In this study, McrBC – an endonuclease which is
sensitive to methylcytosine – was used to detect DNA methylation status in some regions of the
OsSOS1 gene in two rice cultivars: a salt sensitive cultivar Nipponbare and a salt tolerant cultivar
Pokkali under saline condition. McrBC-PCR revealed two hypermethylation regions in the middle
of OsSOS1 gene while the other two showed hypomethylation. Furthermore, the methylation status
was the same in shoot and in root tissues, and had no significant change under salt condition
compared to control condition in both investigated cultivars. Result of bisulfite sequencing showed
that the hypermethylation only occurred in CpG sites but not CHG and CHH contexts.