title: Creating drought- and salt-tolerant cotton by overexpressing a vacuolar pyrophosphatase gene.
abstract: Increased expression of an Arabidopsis vacuolar pyrophosphatase gene, AVP1, leads to increased drought and salt tolerance in transgenic plants, which has been demonstrated in laboratory and field conditions. The molecular mechanism of AVP1-mediated drought resistance is likely due to increased proton pump activity of the vacuolar pyrophosphatase, which generates a higher proton electrochemical gradient across the vacuolar membrane, leading to lower water potential in the plant vacuole and higher secondary transporter activities that prevent ion accumulation to toxic levels in the cytoplasm. Additionally, overexpression of AVP1 appears to stimulate auxin polar transport, which in turn stimulates root development. The larger root system allows AVP1-overexpressing plants to absorb water more efficiently under drought and saline conditions, resulting in stress tolerance and increased yields. Multi-year field-trial data indicate that overexpression of AVP1 in cotton leads to at least 20% more fiber yield than wild-type control plants in dry-land conditions, which highlights the potential use of AVP1 in improving drought tolerance in crops in arid and semiarid areas of the world.
authors.affiliation: Department of Biological Sciences, Texas Tech University, Lubbock, TX, USA. hong.zhang@ttu.edu
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
authors.forename: Guoxin
authors.initials: G
authors.lastname: Shen
authors.forename: Sundaram
authors.initials: S
authors.lastname: Kuppu
authors.forename: Roberto
authors.initials: R
authors.lastname: Gaxiola
authors.forename: Paxton
authors.initials: P
authors.lastname: Payton
mesh_terms: D029681:Arabidopsis Proteins / Q000235:genetics*; D055864:Droughts; D017343:Genes, Plant / Q000235:genetics; D003368:Gossypium / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development / Q000502:physiology*; D043564:Inorganic Pyrophosphatase / Q000235:genetics*; D010797:Phthalimides / Q000494:pharmacology; D030821:Plants, Genetically Modified; D055049:Salt Tolerance / Q000235:genetics*; D014617:Vacuoles / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics*
chemical_list: D029681:Arabidopsis Proteins; D010797:Phthalimides; C002687:alpha-naphthylphthalamic acid; C505048:AVP1 protein, Arabidopsis; D043564:Inorganic Pyrophosphatase