Abstract:Based on the previous research about Ipomoea pes-caprae cDNA library screening, a full length cDNA encoding dehydrin was characterized and named as IpDHN (GenBank accession:No. KX426069). In order to explore the transcriptional activity of the IpDHN promoter and the characteristics of this promoter region responding to abiotic stresses and ABA, the 5' upstream sequence of IpDHN (974 bp), named as IpDHN-Pro was cloned by genomic walking method, and then was subcloned into plant expression vector, in which GUS is under control of IpDHN-Pro. The transgenic Arabidopsis plants harboring IpDHN-Pro::GUS were checked by GUS staining assay, then the expression of GUS was further detected by qRT-PCR after the transgenic plants were challenged by NaCl, mannitol and ABA. The results showed that the IpDHN-Pro contained several cis-acting elements, including an ABRE, three Myb transcription factor binding sites, a TC-rich repeat, and a Skn-1 motif. The GUS staining and qRT-PCR showed that IpDHN-Pro could drive the stable expression of GUS gene in transgenic Arabidopsis, and this promoter was up-regulated by high salinity, osmotic stress and ABA treatment. Therefore, it was indicated that IpDHN-Pro was a salt/dehydration and ABA induced promoter sequence, and can be applied in plant genetic engineering research aiming at abiotic stress tolerance.
