Molecular mechanism of temperature sensing by the circadian clock of Neurospora crassa
Open Access
- 17 August 2005
- journal article
- Published by Cold Spring Harbor Laboratory in Genes & Development
- Vol. 19 (17) , 1968-1973
- https://doi.org/10.1101/gad.345905
Abstract
Expression levels and ratios of the long (l) and short (s) isoforms of the Neurospora circadian clock protein FREQUENCY (FRQ) are crucial for temperature compensation of circadian rhythms. We show that the ratio of l-FRQ versus s-FRQ is regulated by thermosensitive splicing of intron 6 of frq, a process removing the translation initiation site of l-FRQ. Thermosensitivity is due to inefficient recognition of nonconsensus splice sites at elevated temperature. The temperature-dependent accumulation of FRQ relative to bulk protein is controlled at the level of translation. The 5′-UTR of frq RNA contains six upstream open reading frames (uORFs) that are in nonconsensus context for translation initiation. Thermosensitive trapping of scanning ribosomes at the uORFs leads to reduced translation of the main ORF and allows adjustment of FRQ levels according to ambient temperature.Keywords
This publication has 27 references indexed in Scilit:
- Molecular mechanisms of translational controlNature Reviews Molecular Cell Biology, 2004
- The mammalian circadian timing system: from gene expression to physiologyChromosoma, 2004
- Splicing of the period Gene 3′-Terminal Intron Is Regulated by Light, Circadian Clock Factors, and Phospholipase CMolecular and Cellular Biology, 2004
- Photoperiodism in Neurospora CrassaJournal of Biological Rhythms, 2004
- Seasonal behavior in Drosophila melanogaster requires the photoreceptors, the circadian clock, and phospholipase CProceedings of the National Academy of Sciences, 2004
- Circadian gene expression in mammalian fibroblasts revealed by real-time luminescence reporting: Temperature compensation and dampingProceedings of the National Academy of Sciences, 2003
- Alternative Initiation of Translation and Time-Specific Phosphorylation Yield Multiple Forms of the Essential Clock Protein FREQUENCYCell, 1997
- Thermally Regulated Translational Control of FRQ Mediates Aspects of Temperature Responses in the Neurospora Circadian ClockCell, 1997
- Circadian clock locus frequency: protein encoded by a single open reading frame defines period length and temperature compensation.Proceedings of the National Academy of Sciences, 1994
- The Neurospora clock gene frequency shares a sequence element with the Drosophila clock gene periodNature, 1989