INVESTIGADORES
VIDAL RUSSELL Romina
congresos y reuniones científicas
Título:
Evolution of Gibberellin Biosynthesis and Function in Plants
Autor/es:
ANTEROLA, A.; SHANLE, E.; MANSOURI, K.; SCHUETTE, S.; VIDAL-RUSSELL, R.; COATES, R.; VON SCHWARTZENBERG, K.; RENZAGLIA, K.
Lugar:
Puerto Vallarta, Mexico
Reunión:
Congreso; 19th Annual Meeting of the International Plant Growth Substances Association; 2007
Institución organizadora:
International Plant Growth Substances Association
Resumen:
Gibberellins are essential phytohormones in angiosperms and gymnosperms, as they are required for seed germination, flower development and vegetative growth. In ferns, gibberellins are involved in spore germination, and serve (in some species) as antheridiogens that induce the formation of male gametangia (antheridium). Inspection of the recently sequenced genome of the moss Physcomitrella patens revealed the presence of gibberellin biosynthetic genes, though it appears that this moss uses fewer enzymes than angiosperms do to make gibberellins. An example is the bifunctional diterpene cyclase that has both copalyl diphosphate synthase (CPS) and ent-kaurene synthase (KS) activities. To determine the potential roles of gibberellins in P. patens, the gene encoding the bifunctional diterpene cyclase was heterologously expressed in E. coli, and then tested for its sensitivity to AMO-1618, which is a known CPS and KS inhibitor in higher plants. After confirming that AMO-1618 inhibited the moss bifunctional enzyme, the effects of AMO-1618 on antheridia formation and spore germination of P. patens were tested. Our results show that while antheridia formation in P. patens was not affected by AMO-1618, the germination of its spores was suppressed, suggesting that an ancient role of gibberellins may be in spore germination, rather than in antheridum formation. Hence, in the evolution of land plants, we see a gradual expansion in the biosynthetic pathway leading to gibberellins, as well as in its role in plant development.