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Jay C. Dunlap

Bio: Jay C. Dunlap is an academic researcher from Dartmouth College. The author has contributed to research in topics: Circadian clock & Neurospora crassa. The author has an hindex of 78, co-authored 185 publications receiving 22347 citations. Previous affiliations of Jay C. Dunlap include University of California & Dartmouth–Hitchcock Medical Center.


Papers
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Journal ArticleDOI
Jay C. Dunlap1
22 Jan 1999-Cell
TL;DR: It used to be that research in chronobiology moved biochemical functions [transcriptional activators], the along at a gentlemanly pace, but by mid 1997 the word in determining what the authors perceive as time was PASWCCLK.

2,723 citations

Journal ArticleDOI
24 Apr 2003-Nature
TL;DR: A high-quality draft sequence of the N. crassa genome is reported, suggesting that RIP has had a profound impact on genome evolution, greatly slowing the creation of new genes through genomic duplication and resulting in a genome with an unusually low proportion of closely related genes.
Abstract: Neurospora crassa is a central organism in the history of twentieth-century genetics, biochemistry and molecular biology. Here, we report a high-quality draft sequence of the N. crassa genome. The approximately 40-megabase genome encodes about 10,000 protein-coding genes—more than twice as many as in the fission yeast Schizosaccharomyces pombe and only about 25% fewer than in the fruitfly Drosophila melanogaster. Analysis of the gene set yields insights into unexpected aspects of Neurospora biology including the identification of genes potentially associated with red light photobiology, genes implicated in secondary metabolism, and important differences in Ca21 signalling as compared with plants and animals. Neurospora possesses the widest array of genome defence mechanisms known for any eukaryotic organism, including a process unique to fungi called repeat-induced point mutation (RIP). Genome analysis suggests that RIP has had a profound impact on genome evolution, greatly slowing the creation of new genes through genomic duplication and resulting in a genome with an unusually low proportion of closely related genes.

1,659 citations

Journal ArticleDOI
TL;DR: This study describes a method for rapidly creating knockout mutants in which it makes use of yeast recombinational cloning, Neurospora mutant strains deficient in nonhomologous end-joining DNA repair, custom-written software tools, and robotics.
Abstract: The low rate of homologous recombination exhibited by wild-type strains of filamentous fungi has hindered development of high-throughput gene knockout procedures for this group of organisms. In this study, we describe a method for rapidly creating knockout mutants in which we make use of yeast recombinational cloning, Neurospora mutant strains deficient in nonhomologous end-joining DNA repair, custom-written software tools, and robotics. To illustrate our approach, we have created strains bearing deletions of 103 Neurospora genes encoding transcription factors. Characterization of strains during growth and both asexual and sexual development revealed phenotypes for 43% of the deletion mutants, with more than half of these strains possessing multiple defects. Overall, the methodology, which achieves high-throughput gene disruption at an efficiency >90% in this filamentous fungus, promises to be applicable to other eukaryotic organisms that have a low frequency of homologous recombination.

1,074 citations

Journal ArticleDOI
26 Dec 1997-Cell
TL;DR: In both the phasing of dark expression and the response to light mPer1 is most similar to the Neurospora clock gene frq, consistent with the localization of both light-sensitive and light-insensitive oscillators in this circadian center.

869 citations

Book
10 Dec 2009
TL;DR: This chapter discusses the evolution of Biological Timing from Unicells to Humans, and the Relevance of Circadian Rhythms for Human Welfare.
Abstract: 1. Overview of Biological Timing from Unicells to Humans 2. The Behavioral Ecology and Evolution of Biological Timing Systems 3. Fundamental Properties of Circadian Rhythms 4. Circannual Rhythms and Photoperiodism 5. Functional Organization of Circadian Systems in Multicellular Animals 6. Cell Physiology of Circadian Timing Systems In Metazoan Animals 7. Molecular Biology of Circadian Pacemaker Systems 8. Adapting to Life on a Rotating World at the Gene Expression Level 9. Human Circadian Organization 10. The Relevance of Circadian Rhythms for Human Welfare 11. Looking Forward Glossary Species List

665 citations


Cited by
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Journal ArticleDOI
20 Jan 2000-Nature
TL;DR: This work used three transcriptional repressor systems that are not part of any natural biological clock to build an oscillating network, termed the repressilator, in Escherichia coli, which periodically induces the synthesis of green fluorescent protein as a readout of its state in individual cells.
Abstract: Networks of interacting biomolecules carry out many essential functions in living cells, but the 'design principles' underlying the functioning of such intracellular networks remain poorly understood, despite intensive efforts including quantitative analysis of relatively simple systems Here we present a complementary approach to this problem: the design and construction of a synthetic network to implement a particular function We used three transcriptional repressor systems that are not part of any natural biological clock to build an oscillating network, termed the repressilator, in Escherichia coli The network periodically induces the synthesis of green fluorescent protein as a readout of its state in individual cells The resulting oscillations, with typical periods of hours, are slower than the cell-division cycle, so the state of the oscillator has to be transmitted from generation to generation This artificial clock displays noisy behaviour, possibly because of stochastic fluctuations of its components Such 'rational network design may lead both to the engineering of new cellular behaviours and to an improved understanding of naturally occurring networks

4,488 citations

Journal ArticleDOI
29 Aug 2002-Nature
TL;DR: Circadian rhythms are generated by one of the most ubiquitous and well-studied timing systems and are tamed by a master clock in the brain, which coordinates tissue-specific rhythms according to light input it receives from the outside world.
Abstract: Time in the biological sense is measured by cycles that range from milliseconds to years. Circadian rhythms, which measure time on a scale of 24 h, are generated by one of the most ubiquitous and well-studied timing systems. At the core of this timing mechanism is an intricate molecular mechanism that ticks away in many different tissues throughout the body. However, these independent rhythms are tamed by a master clock in the brain, which coordinates tissue-specific rhythms according to light input it receives from the outside world.

3,962 citations

Journal ArticleDOI
TL;DR: In this paper, the authors describe the rules of the ring, the ring population, and the need to get off the ring in order to measure the movement of a cyclic clock.
Abstract: 1980 Preface * 1999 Preface * 1999 Acknowledgements * Introduction * 1 Circular Logic * 2 Phase Singularities (Screwy Results of Circular Logic) * 3 The Rules of the Ring * 4 Ring Populations * 5 Getting Off the Ring * 6 Attracting Cycles and Isochrons * 7 Measuring the Trajectories of a Circadian Clock * 8 Populations of Attractor Cycle Oscillators * 9 Excitable Kinetics and Excitable Media * 10 The Varieties of Phaseless Experience: In Which the Geometrical Orderliness of Rhythmic Organization Breaks Down in Diverse Ways * 11 The Firefly Machine 12 Energy Metabolism in Cells * 13 The Malonic Acid Reagent ('Sodium Geometrate') * 14 Electrical Rhythmicity and Excitability in Cell Membranes * 15 The Aggregation of Slime Mold Amoebae * 16 Numerical Organizing Centers * 17 Electrical Singular Filaments in the Heart Wall * 18 Pattern Formation in the Fungi * 19 Circadian Rhythms in General * 20 The Circadian Clocks of Insect Eclosion * 21 The Flower of Kalanchoe * 22 The Cell Mitotic Cycle * 23 The Female Cycle * References * Index of Names * Index of Subjects

3,424 citations

Journal ArticleDOI
Jay C. Dunlap1
22 Jan 1999-Cell
TL;DR: It used to be that research in chronobiology moved biochemical functions [transcriptional activators], the along at a gentlemanly pace, but by mid 1997 the word in determining what the authors perceive as time was PASWCCLK.

2,723 citations

Journal ArticleDOI
TL;DR: It is shown that temporal feeding restriction under light-dark or dark-dark conditions can change the phase of circadian gene expression in peripheral cell types by up to 12 h while leaving thephase of cyclic gene expressionIn the SCN unaffected.
Abstract: In mammals, circadian oscillators exist not only in the suprachiasmatic nucleus, which harbors the central pacemaker, but also in most peripheral tissues. It is believed that the SCN clock entrains the phase of peripheral clocks via chemical cues, such as rhythmically secreted hormones. Here we show that temporal feeding restriction under light–dark or dark–dark conditions can change the phase of circadian gene expression in peripheral cell types by up to 12 h while leaving the phase of cyclic gene expression in the SCN unaffected. Hence, changes in metabolism can lead to an uncoupling of peripheral oscillators from the central pacemaker. Sudden large changes in feeding time, similar to abrupt changes in the photoperiod, reset the phase of rhythmic gene expression gradually and are thus likely to act through a clock-dependent mechanism. Food-induced phase resetting proceeds faster in liver than in kidney, heart, or pancreas, but after 1 wk of daytime feeding, the phases of circadian gene expression are similar in all examined peripheral tissues.

2,083 citations