INVESTIGADORES
RUIZ Oscar Adolfo
congresos y reuniones científicas
Título:
Arabidopsis thaliana mutants provide new insights into the role of spermine under long-term salt stress.
Autor/es:
SÁNCHEZ, D. H.; ALET, A. I.; RUIZ, O. A
Lugar:
Recife. Brasil
Reunión:
Congreso; XII Latin American Congress of Plant Physiology,; 2005
Institución organizadora:
Sociedad Brasilera de Fisología Vegetal
Resumen:
Arabidopsis thaliana mutants provide new insights into the role of spermine under long-term salt stress   Sánchez, D.H; Alet A.I; Ruiz O. A.   Unidad de Biotecnología 1, Instituto Tecnológico de Chascomús (IIB-Intech/UNSAM-CONICET); Camino circunvalación laguna, km. 6 cc164 (B7130IWA) Chascomús, Pcia. de Buenos Aires, Argentina (ruiz@intech.gov.ar).   Polyamines (putrescine, spermidine and spermine) are traditionally implicated in the response to environmental cues. In the case of salt stress, free spermine accumulation has been suggested as a particular feature of long-term salinity, while the spermine synthase AtSPMS gene has been reported as inducible by ABA and salt shock. We used the model plant Arabidopsis thaliana with the aim to shed light on the physiological role of free polyamines during salinity, with particular emphasis on spermine. For that purpose, the salt hypersensitive sos mutants and the mutants in the spermine synthases genes were assayed. Results presented herein argue that polyamine metabolism is over-induced in a salt sensitive background, being the increase in free spermidine and spermine a sos-independent response to salinization. AtSPMS gene appears to direct free spermine accumulation, while this tetra-amine is suggested as a strong xenobiotic that elicits typical responses to stress, not necessarily having anti-senescence properties. In addition, spermine synthases mutants appeared to be more sensitive to long-term salinity, supporting the notion that free spermine accumulation represents a physiological trend required for salt stress tolerance that may be involved in the control of ionic balance.