TY - JOUR
T1 - Phytochrome and retrograde signalling pathways converge to antagonistically regulate a light-induced transcriptional network
AU - Martin, Guiomar
AU - Leivar, Pablo
AU - Ludevid, Dolores
AU - Tepperman, James M.
AU - Quail, Peter H.
AU - Monte, Elena
N1 - Funding Information:
This work was supported by grants from the Spanish 'Ministerio de Ciencia e Innovacion' BIO2009-07675, 'Ministerio de Economia' BIO2012-31672, 'Ministerio de Educacion, Cultura y Deporte' PRX12/00631, and from the Generalitat de Catalunya 2009-SGR-206 to E.M.; by 'Comissionat per a Universitats i Recerca del Departament d'Innovacio, Universitats i Empresa' fellowship from the Generalitat de Catalunya (Beatriu de Pinos programme) and Marie Curie IRG PIRG06-GA-2009-256420 grant to P.L.; by grant from 'Ministerio de Economýá' BIO2012-31860 to D.L.; and by grants from the National Institutes of Health (NIH; 2R01GM-047475) and USDA ARS Current Research Information System (5335-21000-032-00D) to P.H.Q.
PY - 2016/5/6
Y1 - 2016/5/6
N2 - Plastid-to-nucleus retrograde signals emitted by dysfunctional chloroplasts impact photomorphogenic development, but the molecular link between retrograde-and photosensory-receptor signalling has remained unclear. Here, we show that the phytochrome and retrograde signalling (RS) pathways converge antagonistically to regulate the expression of the nuclear-encoded transcription factor GLK1, a key regulator of a light-induced transcriptional network central to photomorphogenesis. GLK1 gene transcription is directly repressed by PHYTOCHROME-INTERACTING FACTOR (PIF)-class bHLH transcription factors in darkness, but light-activated phytochrome reverses this activity, thereby inducing expression. Conversely, we show that retrograde signals repress this induction by a mechanism independent of PIF mediation. Collectively, our data indicate that light at moderate levels acts through the plant's nuclear-localized sensory-photoreceptor system to induce appropriate photomorphogenic development, but at excessive levels, sensed through the separate plastid-localized RS system, acts to suppress such development, thus providing a mechanism for protection against photo-oxidative damage by minimizing the tissue exposure to deleterious radiation.
AB - Plastid-to-nucleus retrograde signals emitted by dysfunctional chloroplasts impact photomorphogenic development, but the molecular link between retrograde-and photosensory-receptor signalling has remained unclear. Here, we show that the phytochrome and retrograde signalling (RS) pathways converge antagonistically to regulate the expression of the nuclear-encoded transcription factor GLK1, a key regulator of a light-induced transcriptional network central to photomorphogenesis. GLK1 gene transcription is directly repressed by PHYTOCHROME-INTERACTING FACTOR (PIF)-class bHLH transcription factors in darkness, but light-activated phytochrome reverses this activity, thereby inducing expression. Conversely, we show that retrograde signals repress this induction by a mechanism independent of PIF mediation. Collectively, our data indicate that light at moderate levels acts through the plant's nuclear-localized sensory-photoreceptor system to induce appropriate photomorphogenic development, but at excessive levels, sensed through the separate plastid-localized RS system, acts to suppress such development, thus providing a mechanism for protection against photo-oxidative damage by minimizing the tissue exposure to deleterious radiation.
UR - http://www.scopus.com/inward/record.url?scp=84966769180&partnerID=8YFLogxK
U2 - 10.1038/ncomms11431
DO - 10.1038/ncomms11431
M3 - Article
C2 - 27150909
AN - SCOPUS:84966769180
SN - 2041-1723
VL - 7
JO - Nature Communications
JF - Nature Communications
M1 - 11431
ER -