Characterisation of two cold induced dehydrin genes from Cichorium intybus L.

Two dehydrin genes were identified from a Cichorium intybus EST database. They were among the most abundant sequences obtained from 10 cDNA libraries constructed from chicory roots grown under field conditions. The full length cDNA sequences, designated CiDHN1 and CiDHN2, were 1,176 and 1,055 bp long and encoded predicted polypeptides of 262 and 261 amino acids, respectively. The deduced CiDHN1 protein contains a S-segment and four lysine-rich consensus motifs (K-segments) which represent a typical SK4 structure of dehydrins. The CiDHN2 sequence contains two Y motifs and two K-segments classifying CiDHN2 as Y2K2-type dehydrin. Southern-blotting analysis suggested that CiDHN1 and CiDHN2 are single copy genes. Northern-blotting analysis revealed that both CiDHN genes are expressed in roots and leaves, with seasonal variations in transcript accumulation. The effect of cold on the CiDHN1 and CiDHN2 transcript level was demonstrated. CiDHN1 and CiDHN2 promoter analysis revealed the presence of low temperature-responsive and ABA-responsive elements.