Diversity of Dehydrins in Oleae europaea Plants Exposed to Stress

Dehydrins (DHNs) belong to a large family of proteins whose expression is associated with dehydration during seed maturation, pollen grain development and bud dormancy during winter, as well as plant adaptive response to various stressors. However, the exact roles played by different members of this protein family have not been fully defined. To gain a better understanding of DHN functions in olive plants, we used Western blot analyses to investigate their expression in the leaves of olive plants subjected to wounding, water-deprivation and salt-treatment. Two prominent bands having molecular masses of approximately 40 kD and 42 kD were constitutively expressed, however, their levels increased when the leaves were exposed to stress. Dehydration and salt stress also resulted in the accumulation of two additional proteins, which had molecular masses of approximately 16 kDa and 18 kD. These additional proteins were not detected following wounding. Our results suggest a physiological function for DHNs in olive plants during normal growth conditions and specialized functions during responses to certain types of stress.