scholarly journals Recent advances in understanding regulation of the Arabidopsis circadian clock by local cellular environment

F1000Research ◽  
2020 ◽  
Vol 9 ◽  
pp. 51 ◽  
Author(s):  
Timothy J. Hearn ◽  
Alex A.R. Webb
Keyword(s):  
Circadian Clock ◽  
Small Molecules ◽  
Circadian Oscillator ◽  
Cellular Mechanisms ◽  
Environmental Signals ◽  
The Past ◽  
Genetic Components ◽  
Cellular Environment ◽  
Specific Regulation ◽  
Made In

Circadian clocks have evolved to synchronise an organism’s physiology with the environmental rhythms driven by the Earth’s rotation on its axis. Over the past two decades, many of the genetic components of the Arabidopsis thaliana circadian oscillator have been identified. The interactions between these components have been formulized into mathematical models that describe the transcriptional translational feedback loops of the oscillator. More recently, focus has turned to the regulation and functions of the circadian clock. These studies have shown that the system dynamically responds to environmental signals and small molecules. We describe advances that have been made in discovering the cellular mechanisms by which signals regulate the circadian oscillator of Arabidopsis in the context of tissue-specific regulation.

scholarly journals Idiopathic Pulmonary Comorbidities and Mechanisms

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Maricica Pacurari ◽  
Amal Mitra ◽  
Timothy Turner
Keyword(s):  
Risk Factor ◽  
Scientific Evidence ◽  
New Drugs ◽  
Unknown Etiology ◽  
Disease Development ◽  
Cellular Mechanisms ◽  
Progressive Decline ◽  
The Past ◽  
Disease Mechanisms ◽  
Made In

Idiopathic pulmonary fibrosis (IPF) is a disease with an unknown etiology mainly characterized by a progressive decline of lung function due to the scarring of the tissue deep in the lungs. The overall survival after diagnosis remains low between 3 and 5 years. IPF is a heterogeneous disease and much progress has been made in the past decade in understanding the disease mechanisms that contributed to the development of two new drugs, pirfenidone and nintedanib, which improved the therapeutic management of the disease. The understanding of the cofactors and comorbidities of IPF also contributed to improved management of the disease outcome. In the present review, we evaluate scientific evidence which indicates IPF as a risk factor for other diseases based on the complexity of molecular and cellular mechanisms involved in the disease development and of comorbidities. We conclude from the existing literature that while much progress has been made in understating the mechanisms involved in IPF development, further studies are still necessary to fully understand IPF pathogenesis which will contribute to the identification of novel therapeutic targets for IPF management as well as other diseases for which IPF is a major risk factor.

scholarly journals Photoperiod sensing of the circadian clock is controlled by EARLY FLOWERING 3 and GIGANTEA

2018 ◽  
Author(s):  
Muhammad Usman Anwer ◽  
Amanda Davis ◽  
Seth Jon Davis ◽  
Marcel Quint
Keyword(s):  
Circadian Clock ◽  
Double Mutant ◽  
Genetic Interaction ◽  
Loss Of Function ◽  
Cellular Mechanisms ◽  
Environmental Signals ◽  
Photoperiodic Flowering ◽  
Oscillator Function ◽  
Key Genes ◽  
Central Oscillator

SummaryELF3 and GI are two important components of the Arabidopsis circadian clock. They are not only essential for the oscillator function but are also pivotal in mediating light inputs to the oscillator. Lack of either results in a defective oscillator causing severely compromised output pathways, such as photoperiodic flowering and hypocotyl elongation. Although single loss of function mutants of ELF3 and GI have been well-studied, their genetic interaction remains unclear. We generated an elf3 gi double mutant to study their genetic relationship in clock-controlled growth and phase transition phenotypes. We found that ELF3 and GI repress growth differentially during the night and the day, respectively. Circadian clock assays revealed that ELF3 and GI are essential Zeitnehmers that enable the oscillator to synchronize the endogenous cellular mechanisms to external environmental signals. In their absence, the circadian oscillator fails to synchronize to the light-dark cycles even under diurnal conditions. Consequently, clock-mediated photoperiod-responsive growth and development is completely lost in plants lacking both genes, suggesting that ELF3 and GI together convey photoperiod sensing to the central oscillator. Since ELF3 and GI are conserved across flowering plants and represent important breeding and domestication targets, our data highlight the possibility of developing photoperiod-insensitive crops by adjusting the allelic combination of these two key genes.One sentence summaryELF3 and GI are essential for circadian clock mediated photoperiod sensing.

Impact of a circadian clock on the timing of human sleep

1983 ◽  
Vol 245 (4) ◽  
pp. R497-R504 ◽  
Author(s):  
A. T. Winfree
Keyword(s):  
Circadian Clock ◽  
Sleep Duration ◽  
Sleep Onset ◽  
Temporal Isolation ◽  
The Past ◽  
Human Sleep ◽  
Threshold Process ◽  
Made In

This paper redescribes some recordings of human sleep and waking made in several laboratories during the past decade under conditions of temporal isolation. Since 1972 it has been noticed that sleep duration depends mainly on the timing of prior sleep onset relative to a rhythm of 24- to 25-h duration. The present paper emphasizes four additional points: 1) that the dependence sometimes includes a remarkable discontinuity, 2) that such dependence is characteristic of a rhythmically modulated threshold process; 3) that the rhythm's period gradually changes in some experiments; and 4) that no comparable regularity has been detected in the timing of sleep onset. This last impugns the reliability of models that treat sleep onset and wake onset as complementary but comparable processes.

Visualizing 3D Molecular Structures Using an Augmented Reality App

2019 ◽  
Author(s):  
Kristina Eriksen ◽  
Bjarne Nielsen ◽  
Michael Pittelkow
Keyword(s):  
Augmented Reality ◽  
Small Molecules ◽  
Computer Modelling ◽  
Simple Procedure ◽  
3D Structure ◽  
Molecular Structures ◽  
Free Software ◽  
Programming Skills ◽  
2D Space ◽  
Made In

<p>We present a simple procedure to make an augmented reality app to visualize any 3D chemical model. The molecular structure may be based on data from crystallographic data or from computer modelling. This guide is made in such a way, that no programming skills are needed and the procedure uses free software and is a way to visualize 3D structures that are normally difficult to comprehend in the 2D space of paper. The process can be applied to make 3D representation of any 2D object, and we envisage the app to be useful when visualizing simple stereochemical problems, when presenting a complex 3D structure on a poster presentation or even in audio-visual presentations. The method works for all molecules including small molecules, supramolecular structures, MOFs and biomacromolecules.</p>

South Asian Developmental Crisis (Review Article)

1973 ◽  
Vol 12 (2) ◽  
pp. 181-188
Author(s):  
Rafiq Ahmad
Keyword(s):  
Second World War ◽  
World War ◽  
The Past ◽  
The Great Depression ◽  
Political Independence ◽  
Integrated Theory ◽  
Pass Through ◽  
Developed World ◽  
Second World ◽  
Made In

Like nations and civilizations, sciences also pass through period of crises when established theories are overthrown by the unpredictable behaviour of events. Economics is passing through such a crisis. The challenge thrown by the Great Depression of early 1930s took a decade before Keynes re-established the supremacy of economics. But this supremacy has again been upset by the crisis of poverty in the vast under-developed world which attained political independence after the Second World War. Poverty had always existed but never before had it been of such concern to economists as during the past twenty five years or so. Economic literature dealing with this problem has piled up but so have the agonies of poverty. No plausible and well-integrated theory of economic development or under-development has emerged so far, though brilliant advances have been made in isolated directions.

Enzyme-Instructed Self-assembly in Biological Milieu for Theranostics Purpose

2019 ◽  
Vol 26 (8) ◽  
pp. 1351-1365 ◽  
Author(s):  
Zhentao Huang ◽  
Qingxin Yao ◽  
Simin Wei ◽  
Jiali Chen ◽  
Yuan Gao
Keyword(s):  
Small Molecules ◽  
Precision Medicine ◽  
Self Assembly ◽  
Public Healthcare ◽  
Enzymatic Conversion ◽  
Vaccine Adjuvants ◽  
New Paradigm ◽  
Cancer Treatments ◽  
The Past ◽  
Biological Milieu

Precision medicine is in an urgent need for public healthcare. Among the past several decades, the flourishing development in nanotechnology significantly advances the realization of precision nanomedicine. Comparing to well-documented nanoparticlebased strategy, in this review, we focus on the strategy using enzyme instructed selfassembly (EISA) in biological milieu for theranostics purpose. In principle, the design of small molecules for EISA requires two aspects: (1) the substrate of enzyme of interest; and (2) self-assembly potency after enzymatic conversion. This strategy has shown its irreplaceable advantages in nanomedicne, specifically for cancer treatments and Vaccine Adjuvants. Interestingly, all the reported examples rely on only one kind of enzymehydrolase. Therefore, we envision that the application of EISA strategy just begins and will lead to a new paradigm in nanomedicine.

Mass Spectrometry Techniques: Principles and Practices for Quantitative Proteomics

2020 ◽  
Vol 21 ◽  
Author(s):  
Rocco J. Rotello ◽  
Timothy D. Veenstra
Keyword(s):  
Mass Spectrometry ◽  
Quantitative Proteomics ◽  
Protein Identification ◽  
Dynamic Nature ◽  
Complete Coverage ◽  
The Past ◽  
Proteome Level ◽  
A Cell ◽  
Quantitative Changes ◽  
Made In

: In the current omics-age of research, major developments have been made in technologies that attempt to survey the entire repertoire of genes, transcripts, proteins, and metabolites present within a cell. While genomics has led to a dramatic increase in our understanding of such things as disease morphology and how organisms respond to medications, it is critical to obtain information at the proteome level since proteins carry out most of the functions within the cell. The primary tool for obtaining proteome-wide information on proteins within the cell is mass spectrometry (MS). While it has historically been associated with the protein identification, developments over the past couple of decades have made MS a robust technology for protein quantitation as well. Identifying quantitative changes in proteomes is complicated by its dynamic nature and the inability of any technique to guarantee complete coverage of every protein within a proteome sample. Fortunately, the combined development of sample preparation and MS methods have made it capable to quantitatively compare many thousands of proteins obtained from cells and organisms.

Evidence-based Assessment

2010 ◽  
pp. 76-98
Author(s):  
John Hunsley ◽  
Eric J. Mash
Keyword(s):  
Decision Making ◽  
Clinical Assessment ◽  
Assessment Process ◽  
Evidence Based ◽  
The Past ◽  
Specific Assessment ◽  
The Many ◽  
Selection Of ◽  
Made In

Evidence-based assessment relies on research and theory to inform the selection of constructs to be assessed for a specific assessment purpose, the methods and measures to be used in the assessment, and the manner in which the assessment process unfolds. An evidence-based approach to clinical assessment necessitates the recognition that, even when evidence-based instruments are used, the assessment process is a decision-making task in which hypotheses must be iteratively formulated and tested. In this chapter, we review (a) the progress that has been made in developing an evidence-based approach to clinical assessment in the past decade and (b) the many challenges that lie ahead if clinical assessment is to be truly evidence-based.

scholarly journals Alternative approaches to target Myc for cancer treatment

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Chen Wang ◽  
Jiawei Zhang ◽  
Jie Yin ◽  
Yichao Gan ◽  
Senlin Xu ◽  
...  
Keyword(s):  
Cancer Treatment ◽  
Small Molecules ◽  
Drug Target ◽  
The Past ◽  
Physiological Processes ◽  
Alternative Approaches ◽  
Global Transcriptome ◽  
Factor C ◽  
Signaling Modules ◽  
Druggable Targets

AbstractThe Myc proto-oncogene family consists of three members, C-MYC, MYCN, and MYCL, which encodes the transcription factor c-Myc (hereafter Myc), N-Myc, and L-Myc, respectively. Myc protein orchestrates diverse physiological processes, including cell proliferation, differentiation, survival, and apoptosis. Myc modulates about 15% of the global transcriptome, and its deregulation rewires the cellular signaling modules inside tumor cells, thereby acquiring selective advantages. The deregulation of Myc occurs in >70% of human cancers, and is related to poor prognosis; hence, hyperactivated Myc oncoprotein has been proposed as an ideal drug target for decades. Nevertheless, no specific drug is currently available to directly target Myc, mainly because of its “undruggable” properties: lack of enzymatic pocket for conventional small molecules to bind; inaccessibility for antibody due to the predominant nucleus localization of Myc. Although the topic of targeting Myc has actively been reviewed in the past decades, exciting new progresses in this field keep emerging. In this review, after a comprehensive summarization of valuable sources for potential druggable targets of Myc-driven cancer, we also peer into the promising future of utilizing macropinocytosis to deliver peptides like Omomyc or antibody agents to intracellular compartment for cancer treatment.

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