IBR   13079
INSTITUTO DE BIOLOGIA MOLECULAR Y CELULAR DE ROSARIO
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Functional Analysis of the GDH promoter
Autor/es:
FERRARO G., BORTOLITTI S., VALLE E. M.
Lugar:
Mar del Plata
Reunión:
Congreso; XLIII Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB); 2007
Resumen:
In ripening tomato fruits a strong induction of
NAD(H)-dependent glutamate dehydrogenase (GDH) paralleled the increase of
glutamate concentration. The role of GDH during this process is still a matter
of discussion. GDH catalyses a reversible reaction for the reductive amination
of α-ketoglutarate to glutamate. Previously in our lab a full-length gene
encoding the β-subunit of GDH and its corresponding promoter were isolated. In
silico analysis of 3.7-kbp gdh putative promoter revealed two classes of motif,
one associated with physiological processes like ripening, nitrogen and carbon
metabolisms, and another class associated with stress processes like drought
and pathogen infection. We cloned several promoter length fragments fusion to
the β-glucuronidase (GUS) reporter gene in order to test the in vivo response
of this promoter. Fragments of 200, 500 y 900 bp of gdh promoter were
introduced in pBI101 plasmid. Arabidopsis plants were transformed by floral dip
with these clones and the transgenic lines were subjected to several treatments
including ABA, SA, ethephon, carbon and nitrogen sources. We found that the gdh
promoter clones reacted differently to the assayed treatments, corroborating
some of the predictive cis-acting elements. This analysis revealed that
physiological conditions and stress factors are involved in the regulation of
gdh expression.