On the relationships between lncrnas and other orchestrating regulators: Role of the circadian system

Abstract

Numerous lncRNAs exhibit circadian rhythms, sometimes with high amplitudes. Therefore, they are controlled by cellular circadian oscillators. However, they also seem to influence circadian clocks, as shown by the important core oscillator gene Per2, at which antiphasic rhythms of Per2 mRNA and its antisense lncRNA are generated. Circadian cycles have also been described for enhancer and super-enhancer lncRNAs. Various lncRNAs are involved in the generation of the rhythm in the pineal gland, which secretes the circadian regulator molecule, melatonin. This compound acts pleiotropically in presumably all tissues and nucleate cells. At least, some of its effects are mediated by sirtuin 1 (SIRT1). SIRT1 enhances circadian amplitudes as an accessory oscillator component and participates in numerous regulation mechanisms. The interrelated actions of circadian oscillators, melatonin and SIRT1 apparently control at least 30% of all coding genes, processes that involve numerous lncRNAs.