ANALYSIS OF AN ABSCISIC ACID (ABA)-RESPONSIVE GENE PROMOTER BELONGING TO THE ASR GENE FAMILY FROM TOMATO IN HOMOLOGOUS AND HETEROLOGOUS SYSTEMS

MAGDALENA ROSSI; FERNANDO CARRARI; JOSÉ LUIS CABRERA-PONCE; CECILIA VAZQUEZ-ROVERE; LUIS HERRERA-ESTRELLA; GUSTAVO EDUARDO GUDESBLAT; NORBERTO DANIEL IUSEM

MOLECULAR AND GENERAL GENETICS

Springer

Año: 1998 vol. 258 p. 1 - 8

0026-8925

Asr is a family of genes that maps to chromosome 4 of tomato. Asr2, a recently reported member of this family, is believed to be regulated by abscisic acid (ABA), stress and ripening. A genomic Asr2 clone has been fully sequenced, and candidate upstream regulatory elements have been identified. To prove that the promoter region is functional in vivo, we fused it upstream of the beta-glucuronidase (GUS) reporter gene. The resulting chimeric gene fusion was used for transient expression assays in papaya embryogenic calli and leaves. In addition, the same construct was used to produce transgenic tomato, papaya, tobacco, and potato plants. Asr2 upstream sequences showed promoter function in all of these systems. Under the experimental conditions tested, ABA stimulated GUS expression in papaya and tobacco, but not in tomato and potato systems.