Phytochromes are red/far red photosensors regulating numerous developmental programs in plants. Among them phytochrome A (phyA) is essential to enable seedling de-etiolation in continuous far-red (FR) light a condition mimicking the environment under a dense canopy. The ecological relevance of this response is demonstrated by the high mortality rate of phyA mutants germinating in deep vegetational shade. phyA signaling involves a direct interaction of the photoreceptor with members of the bHLH transcription factor family, PIF1 and PIF3 (Phytochrome Interacting Factor). Here we investigated the involvement of PIF4 and PIF5 in phyA signaling and found that they redundantly control de-etiolation in FR light. The pif4pif5 double mutant is hypersensitive to low fluence rates of FR light. This phenotype is dependent on FR light perception by phyA but does not rely on alterations of the phyA level. Our microarrays analysis shows that PIF4 and PIF5 are part of an inhibitory mechanism repressing the expression of some light-responsive genes in the dark and are also needed for full expression of several growth-related genes in the light. Unlike PIF1 and PIF3, PIF4 and PIF5 are not degraded in response to FR light indicating that they are light-regulated by a different mechanism. Our genetic analysis suggests that this is achieved through the sequestration of these PIFs by the closely related bHLH transcription factor HFR1 (long Hypocotyl in FR light).
Phytochrome interacting factors 4 and 5 redundantly limit seedling de-etiolation in continuous far-red light.
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View SamplesPlant hypocotyls elongate in response to darkness. The response to darkness is gated by the circadian clock, such that wild-type plants (Col) only respond to darkness with growth once every 24 hours, whereas arrhythmic lines, such as CCA1-34, will respond to darkness with growth at any time of day. The experiment here was designed to find genes whose expression was correlated with growth. It should also pick up other genes that are gated by the circadian clock or that are direct targets of CCA1.
Rhythmic growth explained by coincidence between internal and external cues.
Age, Specimen part
View SamplesGrowth in dense stands induces shade avoidance responses. Late stages of stand development lead to low red:far-red (R:FR) and low blue light conditions.
Integration of Phytochrome and Cryptochrome Signals Determines Plant Growth during Competition for Light.
Age, Specimen part, Treatment
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Phytochrome interacting factors 4 and 5 control seedling growth in changing light conditions by directly controlling auxin signaling.
Age, Specimen part, Treatment
View SamplesAs sessile organisms plants developed a veriety of adaptive responses to the ever changing environment. One of these responses is the shade avoidance syndrome which is composed of different responses like elongation growth, hyponastic leafs or early flowering to shade (low R/FR). Phytochrcome Interacting Factor 4 and 5 are bHLH transcription factors reported to activate gene expression upon perception of low R/FR. Using this miroarray experiment we identified new genes regulated by PIF4 and PIF5 in response to shade and investigated their genome wide role.
Phytochrome interacting factors 4 and 5 control seedling growth in changing light conditions by directly controlling auxin signaling.
Age, Specimen part, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
TRIM24 Is an Oncogenic Transcriptional Activator in Prostate Cancer.
Cell line, Treatment
View SamplesIn this experiment we are exploring which genes are regulated by TRIM24 in androgen-dependent and castration-resistant prostate cancer cells.
TRIM24 Is an Oncogenic Transcriptional Activator in Prostate Cancer.
Cell line, Treatment
View SamplesDigital gene expression profiling was used to invesigate the differetiated genes between primary mouse hepatic stellate cells infected with AGGF1 adenovirus particles or negative control adenovirus pairticles. Overall design: Primary hepatic stellate cells isolated from mice were cultured in vitro, infected with AGGF1 adenovirus particles or negative control adenovirus particles, at day 8, total RNA were prepared and used for digital gene expression tag profiling.
Angiogenic factor with G patch and FHA domains 1 (Aggf1) regulates liver fibrosis by modulating TGF-β signaling.
Specimen part, Cell line, Subject, Time
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Synovium-Derived MicroRNAs Regulate Bone Pathways in Rheumatoid Arthritis.
Specimen part, Time
View SamplesTo find regulated genes during peak inflammation of rheumatoid arthritis (RA), we have collected synovium from mouse Serum Transfer Arthtitis (STA) model at day 0 (Non Arthritic) and day 10 (Peak Inflammation).
Synovium-Derived MicroRNAs Regulate Bone Pathways in Rheumatoid Arthritis.
Specimen part, Time
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