INVESTIGADORES
MAIALE Santiago Javier
congresos y reuniones científicas
Título:
Avena sativa polyamine biosynthesis under saline stress
Autor/es:
GUIRADO ALEJANDRA; SANCHEZ DIEGO; CUEVAS JUAN C; MAIALE SANTIAGO; RUIZ OSCAR
Lugar:
villa Carlos Paz, Cordoba
Reunión:
Congreso; 28 Reunion anual de la sociedad argentina de investigaciones en bioquimica y biologia molecualr; 2002
Institución organizadora:
Sociedad Argentina de Investigaciones en Bioquimica y Biologia Molecular
Resumen:
Putrescine (Put), spermidine (Spd) and spermine (Spm) form a class of
aliphatic amines that are ubiquitous in living organisms, and have been
implicated in a wide range of biological processes, including plant growth and
development. However, their mode of action remains a matter of speculation.
In recent years, attention has been focused on the involvement of PAs in
response to environmental stresses. In plants, there are general agreement in
consider the arginine decarboxylase (ADS; EC 4.1.1.19) and the Sadenosylmethionine
decarboxylase (SAMDC; EC 4.1.1.50) as key enzyme
playing a decisive role in the regulation of the Pas levels.
In this work, we analyzed the activity of these and other enzymes included in
the catabolic PAs biosynthetic pathway (i.e. di- DAO- and poliaminooxidase-
PAO) in shoots from 9 days old seedlings of Avena sativa under long and
short time expositions to high and low NaCl concentrations. Moreover, we
determined the free polyamine and proline levels simultaneously, in order to
check the osmotic status and their relative importance as osmolytes. We
concluded that: 1) ADC activity and Put levels dont change in short times but
decarboxylase activity increase after five days, while the diamine
concentration shut down. 2) The SAMDC activity show a good correlation with
Spm levels and 3) Long stress exposition resulting in a high tetraamine and
proline accumulation.