PMID- 22303272
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20120823
LR  - 20240404
IS  - 1543-8120 (Electronic)
IS  - 1543-8120 (Linking)
VI  - 9
DP  - 2011
TI  - Phytochrome signaling mechanisms.
PG  - e0148
LID - 10.1199/tab.0148 [doi]
LID - e0148
AB  - Phytochromes are red (R)/far-red (FR) light photoreceptors that play fundamental 
      roles in photoperception of the light environment and the subsequent adaptation 
      of plant growth and development. There are five distinct phytochromes in 
      Arabidopsis thaliana, designated phytochrome A (phyA) to phyE. phyA is 
      light-labile and is the primary photoreceptor responsible for mediating 
      photomorphogenic responses in FR light, whereas phyB-phyE are light stable, and 
      phyB is the predominant phytochrome regulating de-etiolation responses in R 
      light. Phytochromes are synthesized in the cytosol in their inactive Pr form. 
      Upon light irradiation, phytochromes are converted to the biologically active Pfr 
      form, and translocate into the nucleus. phyB can enter the nucleus by itself in 
      response to R light, whereas phyA nuclear import depends on two small 
      plant-specific proteins FAR-RED ELONGATED HYPOCOTYL 1 (FHY1) and FHY1-LIKE (FHL). 
      Phytochromes may function as light-regulated serine/threonine kinases, and can 
      phosphorylate several substrates, including themselves in vitro. Phytochromes are 
      phosphoproteins, and can be dephosphorylated by a few protein phosphatases. 
      Photoactivated phytochromes rapidly change the expression of light-responsive 
      genes by repressing the activity of CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1), an E3 
      ubiquitin ligase targeting several photomorphogenesis-promoting transcription 
      factors for degradation, and by inducing rapid phosphorylation and degradation of 
      Phytochrome-Interacting Factors (PIFs), a group of bHLH transcription factors 
      repressing photomorphogenesis. Phytochromes are targeted by COP1 for degradation 
      via the ubiquitin/26S proteasome pathway.
FAU - Li, Jigang
AU  - Li J
FAU - Li, Gang
AU  - Li G
FAU - Wang, Haiyang
AU  - Wang H
FAU - Wang Deng, Xing
AU  - Wang Deng X
LA  - eng
GR  - R01 GM047850/GM/NIGMS NIH HHS/United States
GR  - R37 GM047850/GM/NIGMS NIH HHS/United States
PT  - Journal Article
DEP - 20110829
PL  - United States
TA  - Arabidopsis Book
JT  - The arabidopsis book
JID - 101214894
PMC - PMC3268501
EDAT- 2012/02/04 06:00
MHDA- 2012/02/04 06:01
PMCR- 2011/08/29
CRDT- 2012/02/04 06:00
PHST- 2012/02/04 06:00 [entrez]
PHST- 2012/02/04 06:00 [pubmed]
PHST- 2012/02/04 06:01 [medline]
PHST- 2011/08/29 00:00 [pmc-release]
AID - 10.1199/tab.0148 [doi]
PST - ppublish
SO  - Arabidopsis Book. 2011;9:e0148. doi: 10.1199/tab.0148. Epub 2011 Aug 29.