INVESTIGADORES
SANTA CRUZ Diego Mario
congresos y reuniones científicas
Título:
Abscic acid and cGMP are involved in heme oxygenase signalling in soybean plants
Autor/es:
SANTA CRUZ, DM; ZILLI, C; NORIEGA G.O.; YANNARELLI, GG; LOPEZ LECUBE, M; TOMARO ML.; BALESTRASSE, KB
Lugar:
Edinburgo
Reunión:
Congreso; 7th international meeting on heme oxygenases and related enzymes; 2012
Resumen:
Abscisic acid (ABA) is a plant hormone that functions in many plant
developmental processes, including bud dormancy. This hormone is
produced in the roots in response to decreased soil water potential and
other situations in which the plant may be under stress. Afterwards, it
translocates to the leaves, where it rapidly alters the osmotic
potential of stomatal guard cells, causing them to shrink and stomata to
close. Cyclic guanosine 3,5 monophosphate (cGMP) is an important second
messenger in animals, and is emerging as a player in regulatory
functions in plants. In this study, we investigated the role of cGMP in
seed germination in soybean.
Aims. Experiments were carried out in order to elucidate the role of
cGMP and abscicic acid, a well known plant hormone involved in
developemental processes, in the HO-1 signalling pathway in soybean
plants.
Methods and Results .Soybean seeds were pretreated with different
concentrations of a membrane-permeant analogue of cGMP (100µM)
(8-Br-cGMP), hemin (20µM) (an inducer of heme oxygenase),
Zn-protoporphyrin (20µM) (ZnPPIX) (specific inhibitor of heme oxygenase)
and abscisic acid (ABA) for 48 h. We demonstrated that both 8-Br-cGMP
and hemine promoted seed germination. Experiments performed in seeds
treated with ZnPPIX demonstrated that heme oxygenase (HO-1) activity is
required for seed germination. Moreover, HO-1 gene expression was
modulated by both cGMP and ABA treatments. When different concentrations
of ABA (0.5, 1 and 2µM) were assessed, the highest concentration
induced plant growth.
Conclusions. These findings highlight on one hand, that cGMP is a
positive regulator and plays a crucial role in soybean seed
germination.and on the other hand; both ABA and cGMP are required for
seed germination. Heme oxigenase-1 activity and expression are affected
by cGMP and ABA indicating not only that both compounds are involved in
its signalling pathway, but that heme degradation plays an important
role in soybean seeds germination.