Molecular characterization of a cryptochrome in Neurospora crassa
Ontology highlight
ABSTRACT:
ORGANISM(S): Neurospora crassa
PROVIDER: GSE14909 | GEO | 2010/03/31
SECONDARY ACCESSION(S): PRJNA112015
REPOSITORIES: GEO
Similar Datasets
Project description:Cryptochromes were identified in plants and animals where they function as either photoreceptors or circadian clock components. In the filamentous fungus Neurospora, the biological function of cryptochrome has not yet been explored. Here, we demonstrate that Neurospora crassa cryptochrome (Nc cry) is a DASH-type of cryptochrome, capable of binding FAD and MTHF, whose transcript and protein levels are both strongly induced by blue light in a wc-1 dependent manner. Although the Nc cry transcript is circadian-regulated and antiphasic to frq, knockout strains of Nc cry appears to have a normal clock phenotype. Whole genome microarray and RT-QPCR analysis confirm that Nc cry is not involved in the signal transduction of either early or late light responses and seems to have no transcriptional regulatory activity under our laboratory conditions. Our study concludes that the only cryptochrome in Neurospora crassa is dispensable for the well-characterized blue light sensing cascade and is not part of the circadian clock system. Keywords: light response Two-color microarray. Alexa Fluor 555 was consistently used to label cDNA synthesized from reference RNA, which is a mixture containing equal amounts of RNA samples harvested from different circadian time points and light treatment durations. The same batch of pooled RNA was used as a reference for each array experiment. Alexa Fluor 647 was used exclusively to label cDNA representing sample RNA.
2010-06-05 | E-GEOD-14909 | biostudies-arrayexpress
Project description:The circadian clock controls many physiological functions in mammals, including responses to cancer therapy, by influencing the pharmacokinetics, efficacy, and toxicity of anticancer drugs. Our objective was to investigate how the timing of administration, as well as the influence of cryptochrome (Cry), a key gene in the circadian clock, impact oxaliplatin's pharmacokinetics and toxicity. Additionally, we aimed to shed light on the underlying mechanism through RNA sequencing.
2023-09-30 | GSE243491 | GEO
Project description:Elucidating the metabolome of the filamentous fungi Neurospora crassa to better understand the link between the circadian clock and metabolism; specifically the role that the clock plays in regulating cellulase production.
2019-01-30 | PXD009682 | Pride
Project description:Circadian clocks are the time-keeping cellular apparatuses that are photoentrained according to the day-night photocycles on Earth 1,2. Cryptochromes (CRYs) are photoreceptors mediating photoentrainment of the circadian clock in plants and animals but how CRYs mediate light regulation of the molecular clock remains unclear 1,3. Here we show that CRYs mediate photoresponses of the circadian clock by regulating the activity of N6-methyladenosine (m6A) RNA methyltransferase and photoresponses of the epitranscriptome. In contrast to the presently known CRY complexome, the CRY2-methyltransferase complex exbibits multivalent interactions and photoresponsive condensation in response to blue light. We show that photoexcited CRY2 undergoes phosphorylation-assisted demixing to form photobodies with the properties of condensed liquid phase, which facilitates assembly of the CRY2-methyltransferase complex in the condensed liquid phase of CRY2 in vivo. The mta mutant impaired in m6A methyltransferase and the cry1cry2 mutant missing CRY photoreceptors share common defects of lengthened circadian period, reduced m6A RNA methylation, and accelerated degradation of mRNAs encoding core components of the molecular clock. These results argue for a photoentrainment mechanism by which blue light elicits liquid-liquid phase separation of the CRY2-methyltransferase complex to regulate m6A mRNA methylation, consequently suppressing mRNA degradation and period lengthening of the circadian clock
2021-07-12 | GSE152465 | GEO
Project description:Circadian clocks are the time-keeping cellular apparatuses that are photoentrained according to the day-night photocycles on Earth 1,2. Cryptochromes (CRYs) are photoreceptors mediating photoentrainment of the circadian clock in plants and animals but how CRYs mediate light regulation of the molecular clock remains unclear 1,3. Here we show that CRYs mediate photoresponses of the circadian clock by regulating the activity of N6-methyladenosine (m6A) RNA methyltransferase and photoresponses of the epitranscriptome. In contrast to the presently known CRY complexome, the CRY2-methyltransferase complex exbibits multivalent interactions and photoresponsive condensation in response to blue light. We show that photoexcited CRY2 undergoes phosphorylation-assisted demixing to form photobodies with the properties of condensed liquid phase, which facilitates assembly of the CRY2-methyltransferase complex in the condensed liquid phase of CRY2 in vivo. The mta mutant impaired in m6A methyltransferase and the cry1cry2 mutant missing CRY photoreceptors share common defects of lengthened circadian period, reduced m6A RNA methylation, and accelerated degradation of mRNAs encoding core components of the molecular clock. These results argue for a photoentrainment mechanism by which blue light elicits liquid-liquid phase separation of the CRY2-methyltransferase complex to regulate m6A mRNA methylation, consequently suppressing mRNA degradation and period lengthening of the circadian clock
2021-07-12 | GSE152464 | GEO
Project description:The plant pathogenic fungus Verticillium dahliae has homologs of the clock genes [Cascant-Lopez et al., 2020], which are well described in Neurospora crassa [Diernfellner et al., 2020]. In N. crassa, frequency (Frq) and the Frq-interacting RNA helicase (Frh) interact and form the Frq-Frh complex [Cheng et al., 2005]. Formation of this complex was described to be still possible but weakened by a single amino acid exchange of arginine 806 of Frh to histidine (Frh^R806H) [Shi et al., 2010; Conrad et al., 2016]. We found that both FRQ and wild-type FRH were required for enhanced conidiation and the light-dependent repression of microsclerotia formation in V. dahliae, but were dispensable for disease induction in tomato plants. Strikingly, the FRH^R806H mutant strain grew similar to the FRQ deletion strain, although transcript and protein levels of Frq were not significantly affected by the FRH^R806H mutation when compared with the wild-type. Therefore, we hypothesized that V. dahliae Frq and Frh form the Frq-Frh complex to regulate V. dahliae development, and that this complex formation is abolished upon the amino acid exchange in the Frh. By the use of protein pull-downs, potential interactions of Frh-GFP or Frh^R806H-GFP with Frq were investigated. While we found evidence for a direct interaction of Frh-GFP and Frq, no proteins were significantly co-enriched with Frh^R806H-GFP. References: Cascant-Lopez, E.; Crosthwaite, S.K.; Johnson, L.J.; Harrison, R.J. No evidence that homologs of key circadian clock genes direct circadian programs of development or mRNA abundance in Verticillium dahliae. Front Microbiol 2020, 11, 1977, doi:10.3389/fmicb.2020.01977. Diernfellner, A.C.R.; Brunner, M. Phosphorylation timers in the Neurospora crassa circadian clock. J Mol Biol 2020, 432, 3449–3465, doi:10.1016/j.jmb.2020.04.004. Cheng, P.; He, Q.; He, Q.; Wang, L.; Liu, Y. Regulation of the Neurospora circadian clock by an RNA helicase. Genes Dev 2005, 19, 234–241, doi:10.1101/gad.1266805. Shi, M.; Collett, M.; Loros, J.J.; Dunlap, J.C. FRQ-interacting RNA helicase mediates negative and positive feedback in the Neurospora circadian clock. Genetics 2010, 184, 351–361, doi:10.1534/genetics.109.111393. Conrad, K.S.; Hurley, J.M.; Widom, J.; Ringelberg, C.S.; Loros, J.J.; Dunlap, J.C.; Crane, B.R. Structure of the frequency‐interacting RNA helicase: a protein interaction hub for the circadian clock. EMBO J 2016, 35, 1707–1719, doi:10.15252/embj.201694327.
2023-07-12 | PXD041716 | Pride
Project description:Circadian rhythms are daily oscillations in metabolism and physiology and are generated by the circadian clock. In fruit fly Drosophila, the circadian clock is generated by a transcription-translation feedback loop in which the positive arm components Clock and Cycle activate the expression of the Period and Timeless genes of negative arm, as well as other circadian clock-regulated genes. After being retained in the cytoplasm, the Period and Timeless proteins then migrate to the nucleus to inhibit the Clock/Cycle transactivity by protein-protein interactions (PPIs). The endogenous circadian clock is synchronized with the geological (solar) clock via photoreceptors. Drosophila Cryptochrome protein functions as a circadian photoreceptor. In the early morning, exposure of Cryptochrome to light causes a conformational change in it which results in the formation of new PPIs. Light-activated Cryptochrome interacts with the core clock protein Timeless and the E3 ubiquitin ligase-substrate adaptor protein Jetlag, which results in the ubiquitylation of Timeless by Jetlag-E3 ligase complex and then degradation of Timeless within minutes by proteasome system. Rapid degradation of Timeless and then its partner protein Period, because of its instability in the absence of Timeless, relieves the inhibition on the Clock/Cycle transcription factors suddenly. Therefore, Clock/Cycle-driven expression of circadian clock-regulated genes are induced again, which is the restart of the circadian oscillation or the resetting of the clock. Following Timeless degradation, Cryptochrome is also degraded so the photoreceptor mechanism does not start a new resetting signal until all the required factors are re-synthesized in a circadian manner. Light-dependent degradation of Drosophila Cryptochrome can be observed in Drosophila S2 cell line in culture. In this project, we aimed at finding the interactome of Cryptochrome protein in Drosophila S2 cell line under light and in the dark using proximity labeling method. Because of the fast kinetics of Cryptochrome degradation, we chose the enzymes that can saturate in less than one hour. TurboID (TID) and APEX2 enzymes label proteins with biotin in the proximity even though they work with different mechanisms. They were fused to Cryptochrome protein, and proximity labeling was performed in the dark or under light. We have identified novel light-dependent or -independent interactors of Drosophila Cryptochrome and confirmed some of them using classical coimmunoprecipitation technique.
2024-02-05 | PXD038052 | Pride
Project description:Gould2011 - Temperature Sensitive Circadian
Clock
This model is a temperature sensitive
version of Pokhilko
et al. 2010 (PMID:
20865009),
which is
BIOMD0000000273
in BioModels.
This model is described in the article:
Network balance via CRY
signalling controls the Arabidopsis circadian clock over
ambient temperatures.
Gould PD, Ugarte N, Domijan M, Costa
M, Foreman J, Macgregor D, Rose K, Griffiths J, Millar AJ,
Finkenstädt B, Penfield S, Rand DA, Halliday KJ, Hall
AJ.
Mol. Syst. Biol. 2013; 9: 650
Abstract:
Circadian clocks exhibit 'temperature compensation', meaning
that they show only small changes in period over a broad
temperature range. Several clock genes have been implicated in
the temperature-dependent control of period in Arabidopsis. We
show that blue light is essential for this, suggesting that the
effects of light and temperature interact or converge upon
common targets in the circadian clock. Our data demonstrate
that two cryptochrome photoreceptors differentially control
circadian period and sustain rhythmicity across the
physiological temperature range. In order to test the
hypothesis that the targets of light regulation are sufficient
to mediate temperature compensation, we constructed a
temperature-compensated clock model by adding passive
temperature effects into only the light-sensitive processes in
the model. Remarkably, this model was not only capable of full
temperature compensation and consistent with mRNA profiles
across a temperature range, but also predicted the
temperature-dependent change in the level of LATE ELONGATED
HYPOCOTYL, a key clock protein. Our analysis provides a
systems-level understanding of period control in the plant
circadian oscillator.
This model is hosted on
BioModels Database
and identified by:
BIOMD0000000564.
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.
2010-10-21 | BIOMD0000000564 | BioModels
Project description:The daily organisation of most mammalian cellular functions is attributed to circadian regulation of clock-controlled protein expression, driven by daily cycles of CRYPTOCHROME-dependent transcriptional feedback repression. To test this, we used quantitative mass spectrometry to compare wild type and CRY-deficient fibroblasts under constant conditions. In CRY-deficient cells, we found that temporal variation in protein, phosphopeptide, and K+ abundance was at least as great as wild type controls. Most strikingly. the extent of temporal variation within either genotype was much smaller than overall differences in proteome composition between WT and CRY-deficient cells. This proteome imbalance in CRY-deficient cells and tissues was associated with increased susceptibility to proteotoxic stress, which impairs circadian robustness, and may contribute to the wide-ranging phenotypes of CRY-deficient mice. Rather than generating largescale daily variation in proteome composition, we suggest it is plausible that the various transcriptional and post-translational functions of CRY proteins ultimately act to promote protein and osmotic homeostasis against daily perturbation.
2021-11-19 | PXD019499 | Pride
Project description:Circadian pace is modulated by light intensity, known as the Aschoff’s rule, with largely unrevealed mechanisms. Here we report that photoreceptor CRY2 mediates blue light input to circadian clock by directly interacting with clock core component PRR9 in blue light dependent manner. This physical interaction dually blocks the accessibility of PRR9 protein to its co-repressor TPL/TPRs and the resulting kinase PPKs. Notably, phosphorylation of PRR9 by PPKs is critical for its DNA binding and repressive activity, hence to ensure proper circadian speed. Given the labile nature of CRY2 in strong blue light, our findings provide a mechanistic explanation for Aschoff’s rule in plants, i.e., blue light triggers CRY2 turnover in proportional to its intensity, which accordingly releasing PRR9 to fine tune circadian speed. Our findings not only reveal a novel network mediating light input into circadian clock, but also unmask a mechanism by which Arabidopsis circadian clock sensing light intensity.
2022-10-06 | PXD035252 | Pride