PERSONAL DE APOYO
GIAMMARIA Veronica
artículos
Título:
Characterization of StABF1, a stress-responsive bZIP
Autor/es:
MARIA NOELIA MUÑIZ GARCIA; VERÓNICA GIAMMARIA; CAROLINA GRANDELLIS; MARIA TERESA TELLEZ IÑON; RITA M. ULLOA; DANIELA CAPIATI
Revista:
PLANTA
Editorial:
SPRINGER
Referencias:
Año: 2011
ISSN:
0032-0935
Resumen:
ABF/AREB bZIP transcription factors mediate
plant abiotic stress responses by regulating the expression of
stress-related genes. These proteins bind to the abscisic acid
(ABA)-responsive element (ABRE), which is the major
cis-acting regulatory sequence in ABA-dependent gene
expression. In an effort to understand the molecular mechanisms
of abiotic stress resistance in cultivated potato
(Solanum tuberosum L.), we have cloned and characterized
an ABF/AREB-like transcription factor from potato, named
StABF1. The predicted protein shares 4557% identity with
A. thaliana ABFs proteins and 96% identity with the S. lycopersicum
SlAREB1 and presents all of the distinctive
features of ABF/AREB transcription factors. Furthermore,
StABF1 is able to bind to the ABRE in vitro. StABF1 gene is
induced in response to ABA, drought, salt stress and cold,
suggesting that it might be a key regulator of ABA-dependent
stress signaling pathways in cultivated potato. StABF1
is phosphorylated in response to ABA and salt stress in a
calcium-dependent manner, and we have identified a potato
CDPK isoform (StCDPK2) that phosphorylates StABF1 in
vitro. Interestingly, StABF1 expression is increased during
tuber development and by tuber-inducing conditions (high
sucrose/nitrogen ratio) in leaves. We also found that StABF1
calcium-dependent phosphorylation is stimulated by tuberinducing
conditions and inhibited by gibberellic acid, which
inhibits tuberization.