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ENTRAINMENT BY PHOTORECEPTORS. "Synchronization of circadian clocks to light–dark cycles (often described as entrainment) is mediated by the action of multiple photoreceptors. In Arabidopsis, this includes at least four of the five phytochromes." https://lnkd.in/d_f7kfY View in LinkedIn

CIRCADIAN CHARACTERISTICS. "These rhythms all share the same fundamental properties: (i) their ability to become entrained, or synchronized, to diurnal changes in environmental conditions; (ii) persistence upon transfer to constant conditions; and (iii) a constant period over the physiological range of temperatures." https://lnkd.in/d_f7kfY View in LinkedIn

INTERLOCKING LOOPS. "Evidence is accumulating that the plant circadian clock comprises additional interlocking feedback loops, similar to those described in animal and fungal clocks." https://lnkd.in/d_f7kfY View in LinkedIn

TRANSCRIPTION PRESENCE. "Circadian control of transcription is widespread, and the list of plant genes regulated by the circadian clock is extensive. Microarray analyses suggest that ∼10% of all Arabidopsis genes regulated at the level of mRNA abundance and have identified multiple metabolic pathways under circadian control." https://lnkd.in/d4JRQbh View in LinkedIn

CLOCK CYCLE. "Accumulation of the TOC1 protein at night promotes transcription from the LHY and CCA1 promoters, thus initiating a new cycle." https://lnkd.in/d_f7kfY View in LinkedIn

FRAGMENT FROM NATURE continues for the second of three weekends on the theme of plant clocks, why they exist, and how they work. These mechanisms are ubiquitous across taxa, and are sophisticated in construction. In many (or most) cases, when external stimuli are removed, they keep ticking. Living things, it seems, are obsessed with time, and have put a lot of ingenuity into marking its passage. I shall refrain from quoting TS Eliot. View in LinkedIn

CLOCK GENES. "Expression of the LHY and CCA1 mRNA levels oscillates and levels of both transcripts peak shortly after dawn. The LHY and CCA1 proteins also are synthesized rhythmically with a lag of approximately 2 h after their cognate mRNAs. Both transcription factors bind to a promoter element known as the evening element and act to inhibit transcription of evening-specific genes, including TOC1. In the evening, the level of both repressors declines and transcription of the TOC1 gene resumes." https://lnkd.in/d_f7kfY View in LinkedIn

POSSIBILITY OF LIFE TRANSITION. "Upon observing the seemingly unlimited complexity and variety of Life's evolving patterns, it becomes almost impossible to refrain from imagining, along with Conway, that, were the game really to be played on an infinite lattice, there must surely arise true living ‘life-forms’, perhaps themselves evolving into more complex, possibly sentient, ‘organisms’." https://lnkd.in/d3B2FKW View in LinkedIn

FEEDBACK LOOPS. "The circadian oscillator of higher plants comprises transcriptional– translational feedback loops similar to those described earlier for fungal and animal clocks." https://lnkd.in/d_f7kfY View in LinkedIn

CLOCK CENTRAL. "In plants, the circadian clock controls expression of approximately 6% of the transcriptome. This includes genes encoding components of all major metabolic pathways as well as genes involved in hormone biosynthesis, photoreceptors and floral regulators such as CO, FT and GI." https://lnkd.in/d_f7kfY View in LinkedIn