RNA-binding proteins and circadian rhythms in Arabidopsis thaliana

• Published in: Philosophical transactions of the Royal Society of London. Series B. Biological sciences Vol. 356; no. 1415; pp. 1755 - 1759
• Main Author: Staiger, Dorothee
• Format: Journal Article
• Language: English
• Published: England The Royal Society 29-11-2001
• Subjects: Arabidopsis; Arabidopsis - physiology; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Circadian Rhythm; Circadian Rhythm - physiology; Control loops; Drosophila; Feedback, Physiological; Gene expression regulation; Gene Expression Regulation, Plant; Genes; Germin-Like Protein; Messenger RNA; Negative feedback; Plant Clocks; Plant Proteins - genetics; Plant Proteins - metabolism; Plants; RNA; RNA binding protein; RNA binding proteins; RNA-Binding Proteins - genetics; RNA-Binding Proteins - metabolism
• ISSN: 0962-8436; 1471-2970
• DOI: 10.1098/rstb.2001.0964

An Arabidopsis transcript preferentially expressed at the end of the daily light period codes for the RNA-binding protein AtGRP7. A reverse genetic approach in Arabidopsis thaliana has revealed its role in the generation of circadian rhythmicity: AtGRP7 is part of a negative feedback loop through which it influences the oscillations of its own transcript. Biochemical and genetic experiments indicate a mechanism for this autoregulatory circuit: Atgrp7 gene transcription is rhythmically activated by the circadian clock during the day. The AtGPR7 protein accumulates with a certain delay and represses further accumulation of its transcript, presumably at the post-transcriptional level. In this respect, the AtGRP7 feedback loop differs from known circadian oscillators in the fruitfly Drosophila and mammals based on oscillating clock proteins that repress transcription of their own genes with a 24 h rhythm. It is proposed that the AtGRP7 feedback loop may act within an output pathway from the Arabidopsis clock.