CGMP AND ABSCISIC ACID ARE REQUIRED FOR SEED GERMINATION IN SOYBEAN PLANTS

SANTA CRUZ, DM; POLIZIO, AH; YANNARELLI, GG; BALESTRASSE, KB

Congreso; XLVII Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2011

Cyclic guanosine 3,5 monophosphate (cGMP) is an importantsecond messenger in animals, and is emerging as a player inregulatory functions in plants. In this study, we investigated the roleof cGMP in seed germination in soybean. The seeds were pretreatedwith different concentrations of a membrane-permeant analogue ofcGMP (100μM) (8-Br-cGMP), hemin (20μM) (an inducer of hemeoxygenase), Zn-protoporphyrin (20μM) (ZnPPIX) (specificinhibitor of heme oxygenase) and abscisic acid (ABA) for 48 h. Wedemonstrated that both 8-Br-cGMP and hemine promoted seedgermination. Experiments performed in seeds treated with ZnPPIXdemonstrated that heme oxygenase (HO) activity is required forseed germination. When different concentrations of ABA (0.5, 1 and2μM) were assessed, the highest concentration induced plantgrowth. These findings highlight that cGMP is a positive regulatorand plays a crucial role in soybean seed germination. Furthermore,both ABA and cGMP are required for seed germination. Theseresults infer that cGMP is involved in the HO signaling pathway.