INVESTIGADORES
GONZALEZ SCHAIN Nahuel Damian
artículos
Título:
Functional profiling identifies genes involved in organ-specific branches of the PIF3 regulatory network in Arabidopsis
Autor/es:
SENTANDREU M; MARTÍN G; GONZÁLEZ SCHAIN N; LEIVAR P; SOY J; TEPPERMAN JM; QUAIL PH; MONTE E
Revista:
PLANT CELL
Editorial:
AMER SOC PLANT BIOLOGISTS
Referencias:
Lugar: Rockville; Año: 2011 vol. 23 p. 3974 - 3991
ISSN:
1040-4651
Resumen:
The phytochrome (phy)-interacting basic helix-loop-helix transcription
factors (PIFs) constitutively sustain the etiolated state of
dark-germinated seedlings by actively repressing deetiolation in
darkness. This action is rapidly reversed upon light exposure by
phy-induced proteolytic degradation of the PIFs. Here, we combined a
microarray-based approach with a functional profiling strategy and identified four PIF3-regulated genes
misexpressed in the dark (MIDAs) that are novel regulators of seedling
deetiolation. We provide evidence that each one of these four MIDA genes
regulates a specific facet of etiolation (hook maintenance, cotyledon
appression, or hypocotyl elongation), indicating that there is branching
in the signaling that PIF3
relays. Furthermore, combining inferred MIDA gene function from mutant
analyses with their expression profiles in response to light-induced
degradation of PIF3 provides evidence consistent with a model where the action of the PIF3/MIDA regulatory network
enables an initial fast response to the light and subsequently prevents
an overresponse to the initial light trigger, thus optimizing the
seedling deetiolation process. Collectively, the data suggest that at
least part of the phy/PIF system acts through these four MIDAs to
initiate and optimize seedling deetiolation, and that this mechanism
might allow the implementation of spatial (i.e., organ-specific) and temporal responses during the photomorphogenic program.