IFEVA   02662
INSTITUTO DE INVESTIGACIONES FISIOLOGICAS Y ECOLOGICAS VINCULADAS A LA AGRICULTURA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Regulation of input-output relationships in phytochrome A signalling.
Autor/es:
CASAL, JORGE J.
Lugar:
Santiago de Chile
Reunión:
Simposio; II Reunión de Biología Vegetal; 2007
Resumen:
Light
modulates plant growth and development. In particular, phytochrome A mediates
two different photoresponses: the so-called very-low-fluence response (VLFR),
which is required for germination when the seeds are briefly exposed to light
during soil tillage, and the high-irradiance response (HIR), which is required
for seedling de-etiotation and survival under dense plant canopies. The two
response modes of phyA can be observed as discrete photobiological phases for
some processes such as inhibition of hypocotyl growth and LHCB gene expression. The molecular mechanisms involved in the
transition between the VLFR and the HIR with increasing frequency of
phytochrome A excitation are not know. We will provide evidence in favour of a
positive feed-back loop involving a transcription factor as a key component in
the transition between VLFR and HIR.