Main content area

Over-expression of a subunit E1 of a vacuolar H+-ATPase gene (Lm VHA-E1) cloned from the halophyte Lobularia maritima improves the tolerance of Arabidopsis thaliana to salt and osmotic stresses

Dabbous, Amira, Ben Saad, Rania, Brini, Faical, Farhat-Khemekhem, Ameny, Zorrig, Walid, Abdely, Chedly, Ben Hamed, Karim
Environmental and experimental botany 2017 v.137 pp. 128-141
Arabidopsis thaliana, H-transporting ATP synthase, Lobularia maritima, antioxidant activity, drought tolerance, gene overexpression, genes, halophytes, leaves, osmoregulation, osmotic stress, salinity, salt stress, seedlings, sodium, survival rate, transgenic plants, vacuoles, water stress
In order to understand the molecular basis of vacuolar H+-ATPase subunits and reveal their possible role in salt and drought tolerance in plant species, a vacuolar H+-ATPase subunit E1 gene (LmVHA-E1) was isolated from the halophyte Lobularia maritima and over-expressed in the glycophyte Arabidopsis thaliana. Q-RT-PCR demonstrated that the expression of this gene was induced in L. maritima in response to salt stress and PEG-induced osmotic stress. The overexpression of LmVHA-E1 in Arabidopsis thaliana conferred high salt and drought tolerance to transgenic plants. Transgenic Arabidopsis plants showed higher seedling survival rates and better antioxidant activities under salt and drought stress. The analysis of ion content and osmotic potentials indicated that under high salinity the transgenic plants compartmentalized more Na+ and showed enhanced osmotic adjustment in the leaves compared with wild-type plants. Accordingly, the higher levels of expression of different stress related genes such as AtNHX1 AtP5CS, AtCAT, AtSOD, AtPOD and AtLEA, indicated higher levels of activities in sodium sequestration into vacuoles, in osmotic regulation and in ROS scavenging of transgenic plants.