Photosensory perception and signalling in plant cells: new paradigms?
Plants monitor informational light signals using three sensory photoreceptor families: the phototropins, cryptochromes and phytochromes. Recent advances suggest that the phytochromes act transcriptionally by targeting light signals directly to photoresponsive promoters through binding to a transcriptional regulator. By contrast, the cryptochromes appear to act post-translationally, by disrupting extant proteosome-mediated degradation of a key transcriptional activator through direct binding to a putative E3 ubiquitin ligase, thereby elevating levels of the activator and consequently of target gene expression.
Quail
Peter H
PH
Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA. quail@nature.berkeley.edu
D056931:Cryptochromes; D029721:Drosophila Proteins; D005136:Eye Proteins; D005420:Flavoproteins / Q000378:metabolism*; D008025:Ligases / Q000378:metabolism; D017956:Photoreceptor Cells, Invertebrate; D010834:Phytochrome / Q000378:metabolism*; D059828:Plant Cells; D018521:Plant Physiological Phenomena; D010944:Plants / Q000378:metabolism*; D011499:Protein Processing, Post-Translational / Q000502:physiology; D043562:Receptors, G-Protein-Coupled; D015398:Signal Transduction / Q000502:physiology*; D014157:Transcription Factors / Q000378:metabolism*; D044767:Ubiquitin-Protein Ligases
D056931:Cryptochromes; D029721:Drosophila Proteins; D005136:Eye Proteins; D005420:Flavoproteins; D043562:Receptors, G-Protein-Coupled; D014157:Transcription Factors; C119828:cry protein, Drosophila; D010834:Phytochrome; D044767:Ubiquitin-Protein Ligases; D008025:Ligases