Empiric, structural and in silico findings give birth to plausible explanations for the multifunctionality of the wheat dehydrin (DHN-5)

Abstract

The wheat dehydrin DHN-5 represents one of the members of the LEA (Late Embryogenesis Abundant) group 2 family. It has been previously shown to play a fundamental role in plant response and adaptation to abiotic stresses. It has also exhibited heat-protecting effect on enzymatic activities. In the present work, we report a number of findings resulting from experimentation and prediction to understand the molecular mechanism underlying the multifunction that may be attributed or directed by the DHN-5 protein. Our analysis showed that DHN-5 was not fixed on the chromatographic affinity resin (Concanavalin A) and did not react with periodic acid used for the staining of glycosylated proteins. These facts reinforced with prediction tools proved that DHN-5 is not glycosylated. In another hand, DHN-5 showed a shift on SDS-PAGE electrophoretic mobility. Eventually, the proposed 3D model of the DHN-5 reinforces their disordered structure. Fold Index and Gold Plot enhance the fact that DHN-5 is an unfolded protein. On the other hand, DHN-5 possesses the ability to chelate ions, like Na+ (86 %), K+ (64 %), Mg2+ (74 %), Cu2+ (77 %), Co2+ (86 %) and Fe2+ (90 %) and could explain the tolerance of transgenic forms of Arabidopsis thaliana plants, containing the DHN-5 gene, against salinity.