Cloning and expression of a dehydrin-like protein from Pistacia vera L.

A full-length dehydrin-like cDNA clone was obtained from a Pistacia vera L. cDNA library. The clone was sequenced and it was found that the deduced protein consists of 230 amino acids with a molecular weight of 25.87 kDa. The glycine rich protein is highly hydrophilic, contains 47.4% charged amino acids and belongs to the K-n-type of dehydrins. It comprises five repetitive units, each containing the K-segment diagnostic of dehydrins, but no serine tract (S-segment) and no Y-segment. Temporally, accumulation of the dehydrin transcript coincides with accumulation of the protein, which remains high in the bud scales of the inflorescence throughout winter. The dehydrin protein accumulates in the outer leaves (scales) of the inflorescence bud and in the bark of 1-year-old stems. In the buds it is mostly concentrated in the palisade-like cells underneath the epidermis, in the bud and in the inner bark parenchyma. Immunogold labeling revealed that it is a cytoplasmic protein with no specific organellar localization. It is suggested that the dehydrin of pistachio may have a dual function, a role in drought and cold tolerances, as well as serving as a storage protein.