Short sequence motifs enriched in 5’ upstream and UTR regions of A.thaliana genes homologous to potato mRNAs hyper- or hypo-expressed upon hydric stress.

In previous expression profile studies by DNA microarrays we have identified several potato genes whose mRNAs are hyper- or hypo-expressed following of potato protoplast growth in culture conditions that simulate in vivo hydric deprivation. In order to understand whether groups of these genes are transcriptionally co-regulated via common cis-acting sequence elements, we undertook the comparison of their transcriptional regulatory regions by searching the 5’ upstream region for enriched short sequence motifs. Unfortunately, the potato genomic sequence of several of the selected genes is not yet available. Therefore, we decided to perform this analysis by using the genomic sequences of A. thaliana homologous gene counterparts, relying on the conservation across these organisms of transcriptional regulatory networks. By using the MEME/MAST motif discovery tools, we have analysed separately 3 consecutive 200 bp sequence blocks from the 5’ region of each gene. The MEME analysis reveals several short sequence motifs that are significantly enriched in the first two sequence blocks, corresponding to: a) upstream transcription regulatory elements; b) Pol II positioning promoter elements / 5’-UTRs.