The transcriptional repressor OsPRR73 links circadian clock and photoperiod pathway to control heading date in rice

FRACTAL DIMENSION OF THE DROSOPHILA CIRCADIAN CLOCK

Fractals ◽

10.1142/s0218348x11005476 ◽

2011 ◽

Vol 19 (04) ◽

pp. 423-430 ◽

Cited By ~ 3

Author(s):

HASSAN M. FATHALLAH-SHAYKH

Keyword(s):

Fractal Dimension ◽

Circadian Clock ◽

Lyapunov Exponents ◽

Fractal Geometry ◽

Target Genes ◽

Transcriptional Repressor ◽

High Dimensional ◽

Counting Procedure ◽

Box Counting ◽

Direct Target

Fractal geometry can adequately represent many complex and irregular objects in nature. The fractal dimension is typically computed by the box-counting procedure. Here I compute the box-counting and the Kaplan-Yorke dimensions of the 14-dimensional models of the Drosophila circadian clock. Clockwork Orange (CWO) is transcriptional repressor of direct target genes that appears to play a key role in controlling the dynamics of the clock. The findings identify these models as strange attractors and highlight the complexity of the time-keeping actions of CWO in light-day cycles. These fractals are high-dimensional counterexamples of the Kaplan-Yorke conjecture that uses the spectrum of the Lyapunov exponents.

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clockwork orange Encodes a Transcriptional Repressor Important for Circadian-Clock Amplitude in Drosophila

Current Biology ◽

10.1016/j.cub.2007.05.039 ◽

2007 ◽

Vol 17 (12) ◽

pp. 1082-1089 ◽

Cited By ~ 91

Author(s):

Chunghun Lim ◽

Brian Y. Chung ◽

Jena L. Pitman ◽

Jermaine J. McGill ◽

Suraj Pradhan ◽

...

Keyword(s):

Circadian Clock ◽

Transcriptional Repressor

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Functional Analysis of the “Green Revolution” Gene Photoperiod-1 and Its Selection Trends During Bread Wheat Breeding

Frontiers in Plant Science ◽

10.3389/fpls.2021.745411 ◽

2021 ◽

Vol 12 ◽

Author(s):

Yongzhen Wu ◽

Jiahui Liu ◽

Guimei Hu ◽

Huixian Xue ◽

Huiyuan Xu ◽

...

Keyword(s):

Circadian Clock ◽

Plant Height ◽

Association Analysis ◽

Green Revolution ◽

Heading Date ◽

Wheat Breeding ◽

Grain Weight ◽

Genome Wide Association ◽

Thousand Grain Weight ◽

Genome Wide

Flowering is central to the transformation of plants from vegetative growth to reproductive growth. The circadian clock system enables plants to sense the changes in the external environment and to modify the growth and development process at an appropriate time. Photoperiod-1 (Ppd-1), which is controlled by the output signal of the circadian clock, has played an important role in the wheat “Green Revolution.” In the current study, we systematically studied the relationship between Ppd-1 haplotypes and both wheat yield- and quality-related traits, using genome-wide association analysis and transgenic strategies, and found that highly appropriate haplotypes had been selected in the wheat breeding programs. Genome-wide association analysis showed that Ppd-1 is associated with significant differences in yield-related traits in wheat, including spike length (SL), heading date (HD), plant height (PH), and thousand-grain weight (TGW). Ppd-1-Hapl-A1 showed increased SL by 4.72–5.93%, whereas Ppd-1-Hapl-B1 and Ppd-1-Hapl-D1 displayed earlier HD by 0.58–0.75 and 1.24–2.93%, respectively, decreased PH by 5.64–13.08 and 13.62–27.30%, respectively, and increased TGW by 4.89–10.94 and 11.12–21.45%, respectively. Furthermore, the constitutive expression of the Ppd-D1 gene in rice significantly delayed heading date and resulted in reduced plant height, thousand-grain weight, grain width (GW), and total protein content. With reference to 40years of data from Chinese wheat breeding, it was found that the appropriate haplotypes Ppd-1-Hapl-A1, Ppd-1-Hapl-B1, and Ppd-1-Hapl-D1 had all been subjected to directional selection, and that their distribution frequencies had increased from 26.09, 60.00, and 52.00% in landraces to 42.55, 93.62, and 96.23% in wheat cultivars developed in the 2010s. A Ppd-B1 methylation molecular marker was also developed to assist molecular wheat breeding. This research is of significance for fully exploring the function of the Ppd-1 gene and its genetic resource diversity, to effectively use the most appropriate haplotypes and to improve crop yield and sustainability.

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ID2 (Inhibitor of DNA Binding 2) Is a Rhythmically Expressed Transcriptional Repressor Required for Circadian Clock Output in Mouse Liver

Journal of Biological Chemistry ◽

10.1074/jbc.m109.013961 ◽

2009 ◽

Vol 284 (46) ◽

pp. 31735-31745 ◽

Cited By ~ 22

Author(s):

Tim Y. Hou ◽

Sarah M. Ward ◽

Joana M. Murad ◽

Nathan P. Watson ◽

Mark A. Israel ◽

...

Keyword(s):

Dna Binding ◽

Circadian Clock ◽

Mouse Liver ◽

Transcriptional Repressor ◽

Inhibitor Of Dna Binding ◽

Circadian Clock Output

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Light-induced phase-delay of the chicken pineal circadian clock is associated with the induction of cE4bp4, a potential transcriptional repressor of cPer2 gene

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.141090998 ◽

2001 ◽

Vol 98 (14) ◽

pp. 8089-8094 ◽

Cited By ~ 68

Author(s):

M. Doi ◽

Y. Nakajima ◽

T. Okano ◽

Y. Fukada

Keyword(s):

Circadian Clock ◽

Transcriptional Repressor ◽

Phase Delay

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A Novel Regulatory Role for the Circadian Clock Protein TOC1 via RNA binding

10.1101/2020.05.06.071340 ◽

2020 ◽

Author(s):

Yi Li ◽

Yong-Gang Chang ◽

Dawn H. Nagel ◽

Tingjian Chen ◽

Matias L Rugnone ◽

...

Keyword(s):

Circadian Clock ◽

Rna Binding ◽

Mutational Analysis ◽

Sequence Similarity ◽

Transcriptional Repressor ◽

Titration Calorimetry ◽

Mobility Shift ◽

Rna Motif ◽

Clock Protein

AbstractThe circadian clock enables plants to predict daily changes of external signals and synchronize them with internal processes, conferring enhanced fitness and growth vigor. The first described Arabidopsis circadian clock protein is TIMING OF CAB EXPRESSION 1 (TOC1), which functions in a transcriptional feedback loop with two myb transcription factors, CIRCADIAN CLOCK-ASSOCIATED 1 (CCA1) and LATE ELONGATED HYPOCOTYL (LHY). Previous studies have shown that TOC1 is a DNA-binding transcriptional repressor of CCA1 and LHY. However, the DNA motifs enriched amongst TOC1 targets share weak sequence similarity and lack consensus, suggesting that TOC1 regulates the expression of its targets through a novel mechanism. Here we show that the TOC1 protein binds directly to RNA via its conserved CCT domain. Using in vitro RNA selection, we identified an RNA motif that is recognized by the TOC1-CCT domain. The TOC1-CCT domain binds to this RNA sequence with nanomolar affinity determined by quantitative electrophoretic mobility shift assays (EMSAs) and isothermal titration calorimetry (ITC). NMR experiments showed that two CCT fragments, CCT533-547 and CCT550-565, use basic residues to bind the RNA motif. Mutational analysis confirmed that lysyl and arginyl residues bind to RNA in a cooperative manner. Furthermore, transiently expressed wildtype and mutant TOC1 in protoplasts demonstrated that RNA binding activity of TOC1 is required for its function as a transcriptional repressor in vivo. Our results reveal a novel regulatory mechanism for TOC1 through RNA binding, suggesting that TOC1 might play key roles as a multi-function protein.

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