“Lotus hairy roots expressing inducible arginine decarboxylase activity”

CHIESA, M. A.; RUIZ, O. A. & SÁNCHEZ, D. H.

BIOTECHNOLOGY LETTERS

Springer Netherlands

Año: 2004 vol. 26 p. 729 - 733

0141-5492

Lotus hairy roots expressing inducible arginine decarboxylase activity María A. Chiesa, Oscar A. Ruiz & Diego H. Sanchez Unidad de Biotecnolog´ia 1, IIB-INTECH/UNSAM-CONICET, Ruta Circunvalaci´ on Laguna, km. 6 cc 164, (7130) Chascom´ us, Provincia de Buenos Aires, Argentina _Author for correspondence (Fax: + 54 2241 424048; E-mail: ruiz@intech.gov.ar) Received 7 January 2004; Revisions requested 23 January 2004; Revisions received 1 March 2004; Accepted 2 March 2004 Key words: arginine decarboxylase, hairy roots, inducible expression, Lotus corniculatus, polyamines Abstract Biotechnological uses of plant cell-tissue culture usually rely on constitutive transgene expression. However, such  expression of transgenes may not always be desirable. In those cases, the use of an inducible promoter could  be an alternative approach. To test this hypothesis, we developed two binary vectors harboring a stress-inducible  promoter from Arabidopsis thaliana, driving the _-glucuronidase reporter gene and the oat arginine decarboxylase. Transgenic hairy roots of Lotus corniculatus were obtained with osmotic- and cold-inducible _-glucuronidase and arginine decarboxylase activities. The increase in the activity of the latter was accompanied by a significant rise in total free polyamines level. Through an organogenesis process, we obtained L. corniculatus transgenic plants avoid-ing deleterious phenotypes frequently associated with the constitutive over-expression of arginine decarboxylation and putrescine accumulation.