Engineering stress tolerance in transgenic plants

• Autorzy: Roxas V P , Wang J. , Lodhi S. , Allen R.D.
• Języki publikacji: EN

Abstrakty

EN

Research in our laboratory has focused on the analysis of the functions of a variety of enzymes that are involved in the scavenging of reactive oxygen intermediates (ROI) such as superoxide radicals (·O⁻₂ ) and hydrogen peroxide (H₂O₂). Recent work has been on transgenic plants that over-express glutathione S-transferases (GST) that also have glutathione peroxidase activity. Transgenic tobacco plants that contain gene constructs that encode two different tobacco GST’s had elevated levels of both GST and GPX activity. Analysis of mature vegetative transgenic tobacco plants that over-express GST/GPX failed to show any increase in paraquat tolerance or protection from photooxidative stress. However, seeds of these GST/GPX-expressing tobacco lines are capable of more rapid germination and seedling growth at low temperatures and at elevated salt concentrations. Reduced levels of lipid peroxidation were noted in GST/GPX-expressing seedling compared to control seedlings under both stressful and non-stressful conditions. In addition, GST/GPX-expressing seedlings significantly accumulated more oxidized glutathione (GSSG) than control seedlings during stress. These characteristics clearly indicate that over-expression of GST/GPX in transgenic seedlings can have substantial effects on their stress tolerance. Furthermore, it appears that this effect is due primarily to the elevated levels of GPX activity.

Słowa kluczowe

EN

salt stress; glutathione S-transferase; chilling stress; stress tolerance; seedling growth; transgenic plant; glutathione; tobacco; plant

• Wydawca: -
• Czasopismo: Acta Physiologiae Plantarum
• Rocznik: 1997
• Tom: 19
• Numer: 4
• Opis fizyczny: p.591-594,fig.

Twórcy

autor

Roxas V P

• Texas Tech University, Lubbock, Texas, USA 79409-3131

autor

Wang J.

autor

Lodhi S.

autor

Allen R.D.

Bibliografia

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