Article

Post-transcriptional control of circadian rhythms

Department of Neuroscience, University of Texas Southwestern Medical Center, NB4.204G, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
Journal of Cell Science (Impact Factor: 5.43). 02/2011; 124(Pt 3):311-20. DOI: 10.1242/jcs.065771
Source: PubMed

ABSTRACT

Circadian rhythms exist in most living organisms. The general molecular mechanisms that are used to generate 24-hour rhythms are conserved among organisms, although the details vary. These core clocks consist of multiple regulatory feedback loops, and must be coordinated and orchestrated appropriately for the fine-tuning of the 24-hour period. Many levels of regulation are important for the proper functioning of the circadian clock, including transcriptional, post-transcriptional and post-translational mechanisms. In recent years, new information about post-transcriptional regulation in the circadian system has been discovered. Such regulation has been shown to alter the phase and amplitude of rhythmic mRNA and protein expression in many organisms. Therefore, this Commentary will provide an overview of current knowledge of post-transcriptional regulation of the clock genes and clock-controlled genes in dinoflagellates, plants, fungi and animals. This article will also highlight how circadian gene expression is modulated by post-transcriptional mechanisms and how this is crucial for robust circadian rhythmicity.

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Available from: Shihoko Kojima
    • "In addition, endothelial cells dedifferentiate by changing micro-environmental context from in vivo to in vitro condition, losing expression of their tissue-specific genes (Lacorre et al., 2004). Based on the observation that cultivated primary endothelial cells retain a 'cellular memory' of the light/dark condition when donor animals were euthanized (Marçola et al., 2013), and miRNAs are involved in the circadian rhythms control (Staiger and Koster, 2011; Kojima et al., 2011), we hypothesized that these cell cultures, obtained from cremaster muscle, contain undifferentiated cells that express a set of miRNAs imposed by environmental lighting responsible for the regulation of the biological programs involved in the different phenotypes previously observed (Marçola et al., 2013). The most common marker used to distinguish progenitors from mature cells is CD133, also designated prominin-1 (Corbeil et al., 2000; Peichev et al., 2000; Alessandri et al., 2004; Belicchi et al., 2004; Richardson et al., 2004; Bussolati et al., 2005; Torrente et al., 2007; Carter et al., 2009; Cui et al., 2013). "
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    • "Daily changes in RNA stability , for instance, could account for such rhythms in a way that even though the gene may be transcribed uniformly throughout the day, the stability of the resulting mRNA would change daily and would be detected as a cycling mRNA. This could be mediated, for instance, by specific proteins/noncoding RNAs (ncRNAs) that interact with the target mRNAs and mediate its rhythmic decay (for examples, see Kojima et al., 2011 "
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    • "The expression of most genes is regulated temporally and spatially. Although most of the regulation of gene expression occurs at the transcription step, the regulation of mRNA stability, localization and modulation of translation are crucial steps, particularly in developmental processes (1) and biological clock systems (2–5). Expression profiles of mRNA or protein are not matched in many cases, implying that translational control is a dynamically regulated mechanism, which is not a silent step (6–8). "
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