An additional negative feedback loop in the classical Belousov-Zhabotinskii reaction: malonyl radical as a second control intermediate

Adipose tissues (AT) expand in response to energy surplus through adipocyte hypertrophy and hyperplasia. The latter, also known as adipogenesis, is a process by which multipotent precursors differentiate to form mature adipocytes. This process is directed by developmental cues that include members of the TGF-β family. Our goal here was to elucidate, using the 3T3-L1 adipogenesis model, how TGF-β family growth factors and inhibitors regulate adipocyte development. We show that ligands of the Activin and TGF-β families, several ligand traps, and the SMAD1/5/8 signaling inhibitor LDN-193189 profoundly suppressed 3T3-L1 adipogenesis. Strikingly, anti-adipogenic traps and ligands engaged the same mechanism of action involving the simultaneous activation of SMAD2/3 and inhibition of SMAD1/5/8 signaling. This effect was rescued by the SMAD2/3 signaling inhibitor SB-431542. By contrast, although LDN-193189 also suppressed SMAD1/5/8 signaling and adipogenesis, its effect could not be rescued by SB-431542. Collectively, these findings reveal the fundamental role of SMAD1/5/8 for 3T3-L1 adipogenesis, and potentially identify a negative feedback loop that links SMAD2/3 activation with SMAD1/5/8 inhibition in adipogenic precursors.

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A Unilateral Negative Feedback Loop Between miR-200 microRNAs and Sox2/E2F3 Controls Neural Progenitor Cell-Cycle Exit and Differentiation

Journal of Neuroscience ◽

10.1523/jneurosci.2124-12.2012 ◽

2012 ◽

Vol 32 (38) ◽

pp. 13292-13308 ◽

Cited By ~ 71

Author(s):

C. Peng ◽

N. Li ◽

Y.-K. Ng ◽

J. Zhang ◽

F. Meier ◽

...

Keyword(s):

Cell Cycle ◽

Negative Feedback ◽

Progenitor Cell ◽

Feedback Loop ◽

Neural Progenitor Cell ◽

Neural Progenitor ◽

Negative Feedback Loop ◽

Cell Cycle Exit

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HIC1 and miR-23~27~24 clusters form a double-negative feedback loop in breast cancer

Cell Death and Differentiation ◽

10.1038/cdd.2016.136 ◽

2016 ◽

Vol 24 (3) ◽

pp. 421-432 ◽

Cited By ~ 20

Author(s):

Yanbo Wang ◽

Hongwei Liang ◽

Geyu Zhou ◽

Xiuting Hu ◽

Zhengya Liu ◽

...

Keyword(s):

Breast Cancer ◽

Negative Feedback ◽

Feedback Loop ◽

Negative Feedback Loop ◽

Double Negative

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An Actomyosin-Arf-GEF Negative Feedback Loop for Tissue Elongation under Stress

Current Biology ◽

10.1016/j.cub.2017.06.038 ◽

2017 ◽

Vol 27 (15) ◽

pp. 2260-2270.e5 ◽

Cited By ~ 23

Author(s):

Junior J. West ◽

Teresa Zulueta-Coarasa ◽

Janna A. Maier ◽

Donghoon M. Lee ◽

Ashley E.E. Bruce ◽

...

Keyword(s):

Negative Feedback ◽

Feedback Loop ◽

Negative Feedback Loop

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THE NATURE OF DEPRESSIVE RUMINATION AND ITS CONNECTION WITH DEPRESSIVE SYMPTOMS

Journal of Social and Clinical Psychology ◽

10.1521/jscp.2020.39.9.761 ◽

2020 ◽

Vol 39 (9) ◽

pp. 761-787

Author(s):

Marta M. Maslej ◽

Benoit H. Mulsant ◽

Paul W. Andrews

Keyword(s):

Factor Analysis ◽

Depressive Symptoms ◽

Problem Solving ◽

Beck Depression Inventory ◽

Negative Feedback ◽

Dynamic Process ◽

Feedback Loop ◽

Negative Feedback Loop ◽

Depressive Rumination ◽

Joint Factor Analysis

Introduction: Researchers have proposed several theories of depressive rumination. To compare among them, we conducted a joint factor analysis. Methods: An online sample (n = 498) completed four rumination questionnaires and the Beck Depression Inventory. We examined associations between emerging factors and depressive symptoms. Results: Most commonly, people ruminated about solving problems in their lives, followed by the causes or consequences of negative situations. They least commonly ruminated about their symptoms and sadness. Thoughts about symptoms and causes or consequences of negative situations uniquely related to depressive symptoms. There was a circular covariance relation between depressive symptoms, thoughts about causes or consequences, and problem-solving, suggesting that symptoms are regulated by a negative feedback loop involving problem-solving. This feedback was not present unless models included thoughts about causes or consequences, suggesting that these thoughts benefit problem-solving. Discussion: Depressive rumination may be a dynamic process involving various thoughts, with different combinations of thoughts having different consequences for depression.

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Systematic Dissection of the Evolutionarily Conserved WetA Developmental Regulator across a Genus of Filamentous Fungi

mBio ◽

10.1128/mbio.01130-18 ◽

2018 ◽

Vol 9 (4) ◽

Cited By ~ 22

Author(s):

Ming-Yueh Wu ◽

Matthew E. Mead ◽

Mi-Kyung Lee ◽

Erin M. Ostrem Loss ◽

Sun-Chang Kim ◽

...

Keyword(s):

Gene Regulatory Network ◽

Filamentous Fungi ◽

Negative Feedback ◽

Regulatory Network ◽

Feedback Loop ◽

Spore Formation ◽

Negative Feedback Loop ◽

Content Type ◽

Asexual Sporulation ◽

Gene Regulatory

ABSTRACTAsexual sporulation is fundamental to the ecology and lifestyle of filamentous fungi and can facilitate both plant and human infection. InAspergillus, the production of asexual spores is primarily governed by the BrlA→AbaA→WetA regulatory cascade. The final step in this cascade is controlled by the WetA protein and governs not only the morphological differentiation of spores but also the production and deposition of diverse metabolites into spores. While WetA is conserved across the genusAspergillus, the structure and degree of conservation of thewetAgene regulatory network (GRN) remain largely unknown. We carried out comparative transcriptome analyses of comparisons betweenwetAnull mutant and wild-type asexual spores in three representative species spanning the diversity of the genusAspergillus:A. nidulans,A. flavus, andA. fumigatus. We discovered that WetA regulates asexual sporulation in all three species via a negative-feedback loop that represses BrlA, the cascade’s first step. Furthermore, data from chromatin immunoprecipitation sequencing (ChIP-seq) experiments inA. nidulansasexual spores suggest that WetA is a DNA-binding protein that interacts with a novel regulatory motif. Several global regulators known to bridge spore production and the production of secondary metabolites show species-specific regulatory patterns in our data. These results suggest that the BrlA→AbaA→WetA cascade’s regulatory role in cellular and chemical asexual spore development is functionally conserved but that thewetA-associated GRN has diverged duringAspergillusevolution.IMPORTANCEThe formation of resilient spores is a key factor contributing to the survival and fitness of many microorganisms, including fungi. In the fungal genusAspergillus, spore formation is controlled by a complex gene regulatory network that also impacts a variety of other processes, including secondary metabolism. To gain mechanistic insights into how fungal spore formation is controlled acrossAspergillus, we dissected the gene regulatory network downstream of a major regulator of spore maturation (WetA) in three species that span the diversity of the genus: the genetic modelA. nidulans, the human pathogenA. fumigatus, and the aflatoxin producerA. flavus. Our data show that WetA regulates asexual sporulation in all three species via a negative-feedback loop and likely binds a novel regulatory element that we term the WetA response element (WRE). These results shed light on how gene regulatory networks in microorganisms control important biological processes and evolve across diverse species.

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