INVESTIGADORES
GONZALEZ SCHAIN Nahuel Damian
artículos
Título:
Graft-transmissible induction of potato tuberization by the microRNA miR172
Autor/es:
MARTIN A; ADAM H; DÍAZ-MENDOZA M; ZURCZAK M; GONZÁLEZ SCHAIN ND; SUÁREZ-LÓPEZ P
Revista:
DEVELOPMENT
Editorial:
COMPANY OF BIOLOGISTS LTD
Referencias:
Lugar: Cambridge; Año: 2009 vol. 136 p. 2873 - 2881
ISSN:
0950-1991
Resumen:
The photoreceptor phytochrome B (PHYB) and the homeodomain protein BEL5 are
involved in the response of potato tuber induction to the photoperiod.
However, whether they act in the same tuberization pathway is unknown. Here we
show the effect of a microRNA, miR172, on this developmental event.
miR172 levels are higher under tuber-inducing short days than under
non-inductive long days and are upregulated in stolons at the onset of
tuberization. Overexpression of this microRNA in potato promotes flowering,
accelerates tuberization under moderately inductive photoperiods and triggers
tuber formation under long days. In plants with a reduced abundance of PHYB,
which tuberize under long days, both BEL5 mRNA and miR172
levels are reduced in leaves and increased in stolons. This, together with the
presence of miR172 in vascular bundles and the graft transmissibility
of its effect on tuberization, indicates that either miR172 might be
mobile or it regulates long-distance signals to induce tuberization.
Consistent with this, plants overexpressing miR172 show increased
levels of BEL5 mRNA, which has been reported to be transmissible
through grafts. Furthermore, we identify an APETALA2-like mRNA
containing a miR172 binding site, which is downregulated in plants
overexpressing miR172 and plants in which PHYB is silenced.
Altogether, our results suggest that miR172 probably acts downstream
of the tuberization repressor PHYB and upstream of the tuberization promoter
BEL5 and allow us to propose a model for the control of tuberization by PHYB,
miR172 and BEL5.