title: Expression of an Arabidopsis vacuolar H+-pyrophosphatase gene (AVP1) in cotton improves drought- and salt tolerance and increases fibre yield in the field conditions.
abstract: The Arabidopsis gene AVP1 encodes a vacuolar pyrophosphatase that functions as a proton pump on the vacuolar membrane. Overexpression of AVP1 in Arabidopsis, tomato and rice enhances plant performance under salt and drought stress conditions, because up-regulation of the type I H+-PPase from Arabidopsis may result in a higher proton electrochemical gradient, which facilitates enhanced sequestering of ions and sugars into the vacuole, reducing water potential and resulting in increased drought- and salt tolerance when compared to wild-type plants. Furthermore, overexpression of AVP1 stimulates auxin transport in the root system and leads to larger root systems, which helps transgenic plants absorb water more efficiently under drought conditions. Using the same approach, AVP1-expressing cotton plants were created and tested for their performance under high-salt and reduced irrigation conditions. The AVP1-expressing cotton plants showed more vigorous growth than wild-type plants in the presence of 200 mM NaCl under hydroponic growth conditions. The soil-grown AVP1-expressing cotton plants also displayed significantly improved tolerance to both drought and salt stresses in greenhouse conditions. Furthermore, the fibre yield of AVP1-expressing cotton plants is at least 20% higher than that of wild-type plants under dry-land conditions in the field. This research indicates that AVP1 has the potential to be used for improving crop's drought- and salt tolerance in areas where water and salinity are limiting factors for agricultural productivity.
authors.affiliation: Department of Biological Sciences, Texas Tech University, Lubbock, TX, USA.
authors.forename: Vijaya
authors.initials: V
authors.lastname: Pasapula
authors.forename: Guoxin
authors.initials: G
authors.lastname: Shen
authors.forename: Sundaram
authors.initials: S
authors.lastname: Kuppu
authors.forename: Julio
authors.initials: J
authors.lastname: Paez-Valencia
authors.forename: Marisol
authors.initials: M
authors.lastname: Mendoza
authors.forename: Pei
authors.initials: P
authors.lastname: Hou
authors.forename: Jian
authors.initials: J
authors.lastname: Chen
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Qiu
authors.forename: Longfu
authors.initials: L
authors.lastname: Zhu
authors.forename: Xianlong
authors.initials: X
authors.lastname: Zhang
authors.forename: Dick
authors.initials: D
authors.lastname: Auld
authors.forename: Eduardo
authors.initials: E
authors.lastname: Blumwald
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
authors.forename: Roberto
authors.initials: R
authors.lastname: Gaxiola
authors.forename: Paxton
authors.initials: P
authors.lastname: Payton
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000502:physiology*; D032561:Cotton Fiber; D055864:Droughts; D018506:Gene Expression Regulation, Plant; D003368:Gossypium / Q000235:genetics* / Q000502:physiology*; D043564:Inorganic Pyrophosphatase / Q000235:genetics* / Q000502:physiology*; D030821:Plants, Genetically Modified; D055049:Salt Tolerance; D013312:Stress, Physiological; D014617:Vacuoles / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; C505048:AVP1 protein, Arabidopsis; D043564:Inorganic Pyrophosphatase