In silico identification of regulatory motifs in co-expressed genes under osmotic stress representing their co-regulation

Osmotic stress is one of the abiotic conditions for plants responsible for osmotic imbalance. The genes have the capability to show differential expression in response to such conditions. In order to understand the role of genes towards multiple stresses simultaneously, a coexpression study is required. In our analysis, the coexpressed genes of Solanum tuberosum showed a positive correlation (0.91) in salt and drought stresses. The genes showing similar expression were grouped into five sub groups. Sub group 2 revealed the highest number of genes and formed a network. The genes of this network were found to be coding for different stress related proteins. The largest portion (25%) of genes was found to be coding for lipoxygenase revealing its role in jasmonic acid pathway responsible for abiotic stresses. The coexpressed genes were further analyzed for their regulation by the same regulatory factor. The results suggest that the coexpressed genes were regulated due to presence of similar binding sites for EREBP/AP2. The gene expression, their coexpression, functional annotation and coregulation were integrated to form a network. This approach could yield that the coexpressed genes are under the control of the same regulatory system thus are coregulated and form a network.