Co-overexpression of AVP1, PP2A-C5, and AtCLCc in Arabidopsis thaliana greatly increases tolerance to salt and drought stresses

Abstract

Abiotic stresses such as salinity and drought impose a severe constraint on global food production, posing a serious challenge in agriculture. Stacking beneficial genes in transgenic crops will likely improve crop yield under abiotic stress conditions. Previous studies showed that individually overexpressing the Arabidopsis vacuolar H + -pyrophosphatase gene AVP1 , the protein phosphatase 2 A catalytic subunit gene PP2A-C5, and the chloride channel protein gene AtCLCc contributed to enhanced salt tolerance and overexpression of AVP1 alone could also improve drought tolerance. We hypothesized that co-overexpressing AVP1 , PP2A-C5, and AtCLCc, would combine the benefits of these three genes, leading to a further increase in salt tolerance in transgenic plants due to the potential synergism of these genes. Indeed, co-overexpression of these three genes in Arabidopsis significantly improved salt and drought tolerance under single as well as under combined salt and drought stresses. The AVP1 / PP2A-C5/AtCLCc co-overexpressing plants displayed robust growth and produced greater amount of biomass as well as viable seeds than wild-type and single gene overexpression plants under saline and drought conditions. This study demonstrates that successful co-overexpression of several well-chosen genes is an effective strategy to achieve greater abiotic stress tolerance and could potentially lead to higher crop yield in regions of the world with saline soil and low precipitation. • Co-overexpression of genes that function synergistically in plant cells could greatly increase salt tolerance in transgenic plants. • This research provides an effective strategy to achieve greater abiotic stress tolerance in plants. • This approach could potentially lead to higher crop yield in semiarid and arid regions of the world