Computational analysis using CisFind of the 3´UTR of cytosolic Glutamine synthetase genes involved in posttranscriptional regulation

Glutamine synthetase (GS) is a key enzyme in nitrogen metabolism in plants. One of the GS isoforms in plants, GS₁ is transcriptionally regulated. Our recent studies show that a soybean GS₁, Gmglnbeta1, gene is posttranscriptionally regulated by its 3´UTR. Using a transgenic approach, we have shown that the 3´UTR of one of the two alfalfa GS₁ genes, MsGS100, plays a similar role as the 3´UTR of Gmglnbeta1 gene in posttranscriptional regulation of a reporter gene while the 3´UTR of the other alfalfa GS₁ gene, MsGS13, does not. The transgenic data was verified using CisFind, and the results showed that the MsGS100 and Gmglnbeta1 with similar posttranscriptional regulation pattern shared common putative cis-elements in their 3´UTRs whereas these elements were absent in MsGS13 3´UTR that did not exhibit similar posttranscriptional regulation pattern. CisFind also detected putative cis-elements that are overrepresented in the 3´UTR of nodule-enhanced GS₁ genes.