Cold acclimation is a multigenic trait that allows hardy plants to develop efficient tolerance mechanisms needed for winter survival. To determine the genetic nature of these mechanisms, several cold-responsive genes of unknown functions were identified from cold-acclimated wheat (Triticum aestivum). To identify the putative functions and structural features of these new genes, integrated genomic approaches of data mining, expression profiling and bioinformatic predictions were used. We herein report the structural heterogeneity of cDNAs, distribution, low temperature-specificity and protein structure of the identified Wcor14 gene. Analyses of the cDNA and genomic DNA sequences by Vector NTI 9.0 software, suggested that, Wcor14 and its related sequences constitute a small multigene family with different intron sizes. The deduced WCOR14 polypeptide, a hydrophobic polypeptide with 140 amino acids (MW=13.5 kDa), showed a high homology to the previously identified wheat and barley COR proteins. No homologous sequences were found in other organisms suggesting that this family is unique to the plant kingdom. The highly homologous signal peptides of WCOR14, BCOR14b and WCS19 contained one putative 14-3-3 protein recognition motif. In this motif, S-residue was predicted as a phosphorylation site and besides this, four other putative phosphorylation sites in WCOR14 were predicted by the NetPhos version 2.0 software. Comparative analyses of gene expression profiling shows that the expression of this gene is correlated with freezing tolerance in cereals.

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