Engineering Drought and Salt Tolerant Soybeans By Overexpressing AVP1, the Vacuole Proton Pump (in progress…)

Salinization and drought conditions are major constraints to global crop production.  Development of drought resistant crop plants has become an important agronomic issue worldwide. Arabidopsis vacuolar H⁺-Pyrophosphatase (AVP1) transports protons from the cytosol into the plant cell vacuole.  Overexpressing the AVP1 gene in Arabidopsis increases vacuolar solute accumulation in plant leaf tissue which leads to increased water retention, conferring drought and salt tolerance (Gaxiola et al., 2001).  Tomato plants engineered to overexpress a vacuolar H⁺-pyrophosphatase also show enhanced tolerance to salinity and drought stress (Park et al., 2005). These findings support the idea that crops overexpressing the AVP1 gene would be valuable in regions where drought and soil with high salt concentration are common.  We are attempting to overexpress AVP1 in soybeans, one of the most agriculturally important crops, using Agrobacterium mediated transformation.