Dataset Information

Tseng2012 - Circadian clock of N.crassa

ABSTRACT: Tseng2012 - Circadian clock of N.crassa A comprehensive model of the circardian clock of fungal Neurospora crassa , which encompasses existing knowledge of the biochemistry of Neurospora clock, is described by Tseng et al. (2012). The model is validated against a wide range of experimental phenotypes and has been used to investigate possible molecular explanations of temperature compensation. This model is described in the article: Comprehensive modelling of the Neurospora circadian clock and its temperature compensation. Tseng YY, Hunt SM, Heintzen C, Crosthwaite SK, Schwartz JM PLoS Comput. Biol. [2012 ; Volume: 8 (Issue: 3 )] Page info: e1002437 Abstract: Circadian clocks provide an internal measure of external time allowing organisms to anticipate and exploit predictable daily changes in the environment. Rhythms driven by circadian clocks have a temperature compensated periodicity of approximately 24 hours that persists in constant conditions and can be reset by environmental time cues. Computational modelling has aided our understanding of the molecular mechanisms of circadian clocks, nevertheless it remains a major challenge to integrate the large number of clock components and their interactions into a single, comprehensive model that is able to account for the full breadth of clock phenotypes. Here we present a comprehensive dynamic model of the Neurospora crassa circadian clock that incorporates its key components and their transcriptional and post-transcriptional regulation. The model accounts for a wide range of clock characteristics including: a periodicity of 21.6 hours, persistent oscillation in constant conditions, arrhythmicity in constant light, resetting by brief light pulses, and entrainment to full photoperiods. Crucial components influencing the period and amplitude of oscillations were identified by control analysis. Furthermore, simulations enabled us to propose a mechanism for temperature compensation, which is achieved by simultaneously increasing the translation of frq RNA and decreasing the nuclear import of FRQ protein. Figure 3 of the reference publication has been reproduced using Copasi 4.8 (Build 35). This model is hosted on BioModels Database and identified by: MODEL1212150000 . To cite BioModels Database, please use: BioModels Database: An enhanced, curated and annotated resource for published quantitative kinetic models . To the extent possible under law, all copyright and related or neighbouring rights to this encoded model have been dedicated to the public domain worldwide. Please refer to CC0 Public Domain Dedication for more information.

SUBMITTER: Yu-yao Tseng

PROVIDER: BIOMD0000000437 | BioModels | 2024-09-02

REPOSITORIES: BioModels

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Comprehensive modelling of the Neurospora circadian clock and its temperature compensation.

Tseng Yu-Yao YY Hunt Suzanne M SM Heintzen Christian C Crosthwaite Susan K SK Schwartz Jean-Marc JM

PLoS computational biology 20120329 3

Circadian clocks provide an internal measure of external time allowing organisms to anticipate and exploit predictable daily changes in the environment. Rhythms driven by circadian clocks have a temperature compensated periodicity of approximately 24 hours that persists in constant conditions and can be reset by environmental time cues. Computational modelling has aided our understanding of the molecular mechanisms of circadian clocks, nevertheless it remains a major challenge to integrate the l ...[more]

PMID: 22496627

Publication: 1/3

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Project description:This a model from the article: Isoform switching facilitates period control in the Neurospora crassa circadian clock. Akman OE, Locke JC, Tang S, Carré I, Millar AJ, Rand DA Mol. Syst. Biol. 2008;Vol 4: 164 18277380 , Abstract: A striking and defining feature of circadian clocks is the small variation in period over a physiological range of temperatures. This is referred to as temperature compensation, although recent work has suggested that the variation observed is a specific, adaptive control of period. Moreover, given that many biological rate constants have a Q(10) of around 2, it is remarkable that such clocks remain rhythmic under significant temperature changes. We introduce a new mathematical model for the Neurospora crassa circadian network incorporating experimental work showing that temperature alters the balance of translation between a short and long form of the FREQUENCY (FRQ) protein. This is used to discuss period control and functionality for the Neurospora system. The model reproduces a broad range of key experimental data on temperature dependence and rhythmicity, both in wild-type and mutant strains. We present a simple mechanism utilising the presence of the FRQ isoforms (isoform switching) by which period control could have evolved, and argue that this regulatory structure may also increase the temperature range where the clock is robustly rhythmic. This model originates from BioModels Database: A Database of Annotated Published Models (http://www.ebi.ac.uk/biomodels/). It is copyright (c) 2005-2011 The BioModels.net Team. For more information see the terms of use . To cite BioModels Database, please use: Li C, Donizelli M, Rodriguez N, Dharuri H, Endler L, Chelliah V, Li L, He E, Henry A, Stefan MI, Snoep JL, Hucka M, Le Novère N, Laibe C (2010) BioModels Database: An enhanced, curated and annotated resource for published quantitative kinetic models. BMC Syst Biol., 4:92.

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Project description:This model 2 described in the supplement of the article below. It is parameterized for the WT at 24°C. To reproduce figure 6 the results have to be rescaled to circadian time by multiplying time by 24/tau, with tau being the period of the free-running oscillator. For the wild-type parameter set tau is equal to 22.7149. Article: Isoform switching facilitates period control in the Neurospora crassa circadian clock. Akman OE, Locke JC, Tang S, Carré I, Millar AJ, Rand DA. Mol Syst Biol. 2008;4:164. Epub 2008 Feb 12. PMID: 18277380, doi:10.1038/msb.2008.5 Abstract: A striking and defining feature of circadian clocks is the small variation in period over a physiological range of temperatures. This is referred to as temperature compensation, although recent work has suggested that the variation observed is a specific, adaptive control of period. Moreover, given that many biological rate constants have a Q(10) of around 2, it is remarkable that such clocks remain rhythmic under significant temperature changes. We introduce a new mathematical model for the Neurospora crassa circadian network incorporating experimental work showing that temperature alters the balance of translation between a short and long form of the FREQUENCY (FRQ) protein. This is used to discuss period control and functionality for the Neurospora system. The model reproduces a broad range of key experimental data on temperature dependence and rhythmicity, both in wild-type and mutant strains. We present a simple mechanism utilising the presence of the FRQ isoforms (isoform switching) by which period control could have evolved, and argue that this regulatory structure may also increase the temperature range where the clock is robustly rhythmic. This model originates from BioModels Database: A Database of Annotated Published Models. It is copyright (c) 2005-2009 The BioModels Team.For more information see the terms of use.To cite BioModels Database, please use Le Novère N., Bornstein B., Broicher A., Courtot M., Donizelli M., Dharuri H., Li L., Sauro H., Schilstra M., Shapiro B., Snoep J.L., Hucka M. (2006) BioModels Database: A Free, Centralized Database of Curated, Published, Quantitative Kinetic Models of Biochemical and Cellular Systems Nucleic Acids Res., 34: D689-D691.

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