Chemical screen identifies a small molecule antagonizing JA-Ile perception and auxin responses

AbstractThe phytohormone JA-Ile regulates many stress responses and developmental processes in plants. A co-receptor complex formed by the F-box protein COI1 and a JAZ repressor perceives the hormone. JA-Ile antagonists are invaluable tools to explore the role of JA-Ile in specific tissues and developmental stages, and to identify novel regulatory processes of the signalling pathway. Using two complementary chemical screens we identified three compounds exhibiting a robust inhibitory effect on both the hormone-mediated COI-JAZ interaction and degradation of JAZ1 and JAZ9 in vivo. One molecule, J4, also restrains specific JA-induced physiological responses in planta, such as JA-mediated gene expression, growth inhibition, chlorophyll degradation and anthocyanin accumulation. Interaction experiments with purified proteins indicate that J4 directly interferes with the formation of the Arabidopsis thaliana COI1-JAZ complex induced by the hormone. The antagonistic effect of J4 on COI1-JAZ also occurs in the liverwort Marchantia polymorpha, suggesting the conservation of its mode of action in land plants. Besides JA signalling, this molecule works as an antagonist of the closely-related auxin signalling pathway, preventing TIR1/Aux-IAA interaction, and auxin responses in planta such as hormone-mediated degradation of an auxin repressor, gene expression and gravitropic response. However, J4 does not affect other hormonal pathways.Altogether, our results show that this dual antagonist competes with JA-Ile and auxin preventing the formation of phylogenetically related receptor complexes. J4 may represent a useful tool to dissect both the JA-Ile and auxin pathways in particular tissues and developmental stages in a reversible way.

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Neural Transcription Correlates of Multimodal Cortical Phenotypes during Development

Cerebral Cortex ◽

10.1093/cercor/bhz271 ◽

2019 ◽

Vol 30 (5) ◽

pp. 2740-2754 ◽

Cited By ~ 1

Author(s):

Diliana Pecheva ◽

Annie Lee ◽

Joann S Poh ◽

Yap-Seng Chong ◽

Lynette P Shek ◽

...

Keyword(s):

Gene Expression ◽

Developmental Stages ◽

Cell Types ◽

Cellular Events ◽

Genetic Mechanisms ◽

Magnetic Resonance Imaging Mri ◽

Regulated Gene Expression ◽

Genetic Signatures ◽

Cell Migration And Proliferation

Abstract During development, cellular events such as cell proliferation, migration, and synaptogenesis determine the structural organization of the brain. These processes are driven in part by spatiotemporally regulated gene expression. We investigated how the genetic signatures of specific neural cell types shape cortical organization of the human brain throughout infancy and childhood. Using a transcriptional atlas and in vivo magnetic resonance imaging (MRI) data, we demonstrated time-dependent associations between the expression levels of neuronal and glial genes and cortical macro- and microstructure. Neonatal cortical phenotypes were associated with prenatal glial but not neuronal gene expression. These associations reflect cell migration and proliferation during fetal development. Childhood cortical phenotypes were associated with neuronal and astrocyte gene expression related to synaptic signaling processes, reflecting the refinement of cortical connections. These findings indicate that sequential developmental stages contribute to distinct MRI measures at different time points. This helps to bridge the gap between the genetic mechanisms driving cellular changes and widely used neuroimaging techniques.

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Revealing the bovine embryo transcript profiles during early in vivo embryonic development

Reproduction ◽

10.1530/rep-08-0533 ◽

2009 ◽

Vol 138 (1) ◽

pp. 95-105 ◽

Cited By ~ 21

Author(s):

Maud Vallée ◽

Isabelle Dufort ◽

Stéphanie Desrosiers ◽

Aurélie Labbe ◽

Catherine Gravel ◽

...

Keyword(s):

Gene Expression ◽

Embryonic Development ◽

Molecular Mechanisms ◽

Developmental Stages ◽

Current Knowledge ◽

Mrna Level ◽

Early Embryonic Development ◽

Bovine Embryo ◽

Rna Content

Gene expression profiling is proving to be a powerful approach for the identification of molecular mechanisms underlying complex cellular functions such as the dynamic early embryonic development. The objective of this study was to perform a transcript abundance profiling analysis of bovine early embryonic development in vivo using a bovine developmental array. The molecular description of the first week of life at the mRNA level is particularly challenging when considering the important fluctuations in RNA content that occur between developmental stages. Accounting for the different intrinsic RNA content between developmental stages was achieved by restricting the reaction time during the global amplification steps and by using spiked controls and reference samples. Analysis based on intensity values revealed that most of the transcripts on the array were present at some point during in vivo bovine early embryonic development, while the varying number of genes detected in each developmental stage confirmed the dynamic profile of gene expression occurring during embryonic development. Pair-wise comparison of gene expression showed a marked difference between oocytes and blastocysts profiles, and principal component analysis revealed that the majority of the transcripts could be regrouped into three main clusters representing distinct RNA abundance profiles. Overall, these data provide a detailed temporal profile of the abundance of mRNAs revealing the richness of signaling processes in early mammalian development. Results presented here provide better knowledge of bovine in vivo embryonic development and contribute to the progression of our current knowledge regarding the first week of life in mammals.

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A versatile genetic tool for post-translational control of gene expression in Drosophila melanogaster

eLife ◽

10.7554/elife.30327 ◽

2017 ◽

Vol 6 ◽

Cited By ~ 7

Author(s):

Sachin Sethi ◽

Jing W Wang

Keyword(s):

Gene Expression ◽

Side Effects ◽

Translational Control ◽

High Efficiency ◽

Developmental Stages ◽

Dynamic Range ◽

In Vivo Studies ◽

Control Of Gene Expression ◽

Regulate Protein

Several techniques have been developed to manipulate gene expression temporally in intact neural circuits. However, the applicability of current tools developed for in vivo studies in Drosophila is limited by their incompatibility with existing GAL4 lines and side effects on physiology and behavior. To circumvent these limitations, we adopted a strategy to reversibly regulate protein degradation with a small molecule by using a destabilizing domain (DD). We show that this system is effective across different tissues and developmental stages. We further show that this system can be used to control in vivo gene expression levels with low background, large dynamic range, and in a reversible manner without detectable side effects on the lifespan or behavior of the animal. Additionally, we engineered tools for chemically controlling gene expression (GAL80-DD) and recombination (FLP-DD). We demonstrate the applicability of this technology in manipulating neuronal activity and for high-efficiency sparse labeling of neuronal populations.

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The receptor-like cytoplasmic kinase MAZZA and CLAVATA-family receptors interact in vivo, together mediating developmental processes in Arabidopsis thaliana

10.1101/2020.11.12.379859 ◽

2020 ◽

Author(s):

Patrick Blümke ◽

Jenia Schlegel ◽

Sabine Becher ◽

Karine Pinto ◽

Rüdiger Simon

Keyword(s):

Gene Expression ◽

Arabidopsis Thaliana ◽

Plasma Membrane ◽

Root Development ◽

Target Gene ◽

Size Control ◽

Receptor Complexes ◽

Cle Peptide ◽

Developmental Contexts

AbstractThe receptor-like kinases (RLKs) CLAVATA1 (CLV1) and BARELY ANY MERISTEMs (BAM1 – 3) form the CLV-family (CLVf), which perceives peptides of the CLV3/EMBRYO SURROUNDING REGION (ESR)-related (CLE) family within various signaling pathways of Arabidopsis thaliana. CLE peptide signaling, which is required for meristem size control, vascular development, or pathogen responses, involves the formation of receptor complexes at the plasma membrane (PM). These complexes comprise RLKs and co-receptors in varying compositions depending on the signaling context and regulate target gene expression, such as WUSCHEL (WUS). How the CLE signal is transmitted intracellularly after perception at the PM is not known.Here, we found that the membrane-associated receptor-like cytoplasmic kinase (RLCK) MAZZA (MAZ) MAZ and additional members of the Pti1-like protein family interact in vivo with CLVf receptors. MAZ, which is widely expressed throughout the plant, localizes to the PM via posttranslational palmitoylation potentially enabling stimulus-triggered protein re-localization. We identified a role for a CLV1/MAZ signaling module during stomatal and root development, and redundancy could potentially mask other phenotypes of maz-1 mutants. We propose that RLCKs such as MAZ mediate CLVf signaling in a variety of developmental contexts, paving the way towards understanding the intracellular processes after CLE peptide perception.

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A versatile genetic tool for post-translational control of gene expression in Drosophila melanogaster

10.1101/130120 ◽

2017 ◽

Author(s):

Sachin Sethi ◽

Jing W. Wang

Keyword(s):

Gene Expression ◽

Side Effects ◽

Translational Control ◽

High Efficiency ◽

Developmental Stages ◽

Dynamic Range ◽

Control Of Gene Expression ◽

Neuronal Populations ◽

Regulate Protein

AbstractSeveral techniques have been developed to manipulate gene expression temporally in intact neural circuits. However, the applicability of current tools developed for in vivo studies in Drosophila is limited by their incompatibility with existing GAL4 lines and side effects on physiology and behavior. To circumvent these limitations, we adopted a strategy to reversibly regulate protein degradation with a small molecule by using a destabilizing domain (DD). We show that this system is effective across different tissues and developmental stages. We further show that this system can be used to control in vivo gene expression levels with low background, large dynamic range, and in a reversible manner without detectable side effects on the lifespan or behavior of the animal. Additionally, we engineered tools for chemically controlling gene expression (GAL80-DD) and recombination (FLP-DD). We demonstrate the applicability of this technology in manipulating neuronal activity and for high-efficiency sparse labeling of neuronal populations.

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Dissecting the membrane-microtubule sensor in grapevine defence

Horticulture Research ◽

10.1038/s41438-021-00703-y ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Pingyin Guan ◽

Wenjing Shi ◽

Michael Riemann ◽

Peter Nick

Keyword(s):

Gene Expression ◽

Experimental System ◽

Inhibitory Effect ◽

Perception System ◽

Diphenylene Iodonium ◽

Plant Microtubules ◽

Defence Responses ◽

Stress Signals ◽

Basal Immunity

AbstractSpecific populations of plant microtubules cooperate with the plasma membrane to sense and process abiotic stress signals, such as cold stress. The current study derived from the question, to what extent this perception system is active in biotic stress signalling. The experimental system consisted of grapevine cell lines, where microtubules or actin filaments are visualised by GFP, such that their response became visible in vivo. We used the bacterial elicitors harpin (inducing cell-death related defence), or flg22 (inducing basal immunity) in combination with modulators of membrane fluidity, or microtubules. We show that DMSO, a membrane rigidifier, can cause microtubule bundling and trigger defence responses, including activation of phytoalexin transcripts. However, DMSO inhibited the gene expression in response to harpin, while promoting the gene expression in response to flg22. Treatment with DMSO also rendered microtubules more persistent to harpin. Paradoxically, Benzylalcohol (BA), a membrane fluidiser, acted in the same way as DMSO. Neither GdCl3, nor diphenylene iodonium were able to block the inhibitory effect of membrane rigidification on harpin-induced gene expression. Treatment with taxol stabilised microtubule against harpin but amplified the response of PAL transcripts. Therefore, the data support implications of a model that deploys specific responses to pathogen-derived signals.

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Antitumor Effects of MRS5698, a Cordycepin Derivative, on Endometrial Cancer Cells

Natural Product Communications ◽

10.1177/1934578x19881564 ◽

2019 ◽

Vol 14 (10) ◽

pp. 1934578X1988156

Author(s):

Pedro Fong ◽

Cheng-I Loi ◽

Wan-Fong U ◽

Chou-I Choi ◽

Tao Yi ◽

...

Keyword(s):

Endometrial Cancer ◽

Inhibitory Effect ◽

Antagonistic Effect ◽

Cordyceps Sinensis ◽

New Drugs ◽

Cancer Drug ◽

Antitumor Effects ◽

Combined Use ◽

Ishikawa Cells

Endometrial cancer drug treatments often produce undesirable effects. Thus, discovering new drugs with fewer side effects is required. Cordycepin is a constituent of Cordyceps sinensis, which has been proven to inhibit tumor growth by stimulating the adenosine A3 receptor (A3R). However, cordycepin is rapidly degraded by adenosine deaminase (ADA) and has a clinically unacceptable short half-life. One of its derivatives, MRS5698, was predicted to exhibit antitumor effects with a poor affinity to ADA by our previous validated in silico experiments. The purpose of this study was to explore the possibilities of using MRS5698 as a novel antitumor agent through experiments on Ishikawa and HEC-1A cells. The detection of inhibition and apoptotic rate of MRS5698 and cisplatin, and their combination, on Ishikawa and HEC-1A cells were performed by MTT assays and flow cytometry, respectively. The inhibition rates of MRS5698 on Ishikawa and HEC-1A cells were both significantly higher than the control groups ( P < 0.05). MRS5698 produced a higher inhibitory effect on HEC-1A cells than on Ishikawa cells with IC50 values of 20.55 and 27.25 μg/mL, respectively. MRS5698 had a stronger inhibitory effect than cisplatin on HEC-1A cells. The Annexin V-FITC/propidium iodide assays demonstrated that the total rate of apoptosis of MRS5698 on HEC-1A cells was higher than that on Ishikawa cells. The results of MTT assay and cellular apoptosis showed that the combined use of MRS5698 and cisplatin produces dose-independent antagonistic effects. MRS5698 produced antitumor effects on both cell lines, which were better than that of cordycepin. However, the combined use of MRS5698 and cisplatin produced an antagonistic effect. A further in vivo study could be considered for investigating the antitumor effects of either MRS5698 monotherapy or MRS5698 in combination with other nonplatinum-based chemotherapeutic drugs in treating endometrial cancer.

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Oligomerization of the extracellular domain of Boss enhances its binding to the Sevenless receptor and its antagonistic effect on R7 induction

Journal of Cell Science ◽

10.1242/jcs.111.6.737 ◽

1998 ◽

Vol 111 (6) ◽

pp. 737-747 ◽

Cited By ~ 1

Author(s):

E.A. Sevrioukov ◽

J.H. Walenta ◽

A. Sunio ◽

M. Phistry ◽

H. Kramer

Keyword(s):

Tyrosine Kinase ◽

Receptor Tyrosine Kinase ◽

Compound Eye ◽

Transmembrane Domain ◽

Extracellular Domain ◽

Antagonistic Effect ◽

Lac Repressor ◽

Receptor Complexes

In the developing compound eye of Drosophila, neuronal differentiation of the R7 photoreceptor cell is induced by the interaction of the receptor tyrosine kinase Sevenless with its ligand Bride of sevenless (Boss), which is expressed on the neighboring R8 cell. Boss is an unusual ligand of a receptor tyrosine kinase: it is composed of a large extracellular domain, a transmembrane domain with seven membrane-spanning segments and a cytoplasmic tail. Expression of a monomeric, secreted form of the extracellular domain of Boss is not sufficient for Sevenless activation, and instead acts as a weak antagonist. Because oligomerization appears to be a critical step in the activation of receptor tyrosine kinases, we used oligomerized forms of the Boss extracellular domain to test their ability to bind to Sevenless in vivo and restore R7 induction in vivo. Oligomerization was achieved by fusion to the leucine zipper of the yeast transcription factor GCN4 or to the tetramerization helix of Lac repressor. Binding of these multivalent proteins to Sevenless could be detected in vitro by immunoprecipitation of cross-linked ligand/receptor complexes and in vivo by receptor-dependent ligand localization. However, neither R8-specific or ubiquitous expression of multivalent Exboss ligands rescued the boss phenotype. Instead, these ligands acted as competitive inhibitors for wild-type Boss protein and thereby suppressed R7 induction. Therefore the role of the transmembrane or cytoplasmic domains of Boss in the activation of the Sev receptor cannot be replaced by oligomerization.

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Preparation of Magnetic Drug Loaded Nanoparticles and Its Anticancer Efficacy Against Nasopharyngeal Carcinoma Cells

Science of Advanced Materials ◽

10.1166/sam.2021.3937 ◽

2021 ◽

Vol 13 (5) ◽

pp. 857-863

Author(s):

Jingjing Chen ◽

Cheng Kang

Keyword(s):

Magnetic Nanoparticles ◽

Nasopharyngeal Carcinoma ◽

Therapeutic Effect ◽

Inhibitory Effect ◽

Antagonistic Effect ◽

Anticancer Efficacy ◽

Normal Tissues ◽

Chemotherapy Agent

As an important drug for the treatment of cancer, cis-diamine dichloroplatinum (CDDP) has poor solubility and antagonistic effect when it is used as a chemotherapy agent alone, leading to the insufficient dose in actual administration. In order to solve the above problems, increase the targeting property of CDDP carrier and prolong the half-life period of CDDP’s sustained-release, it is necessary to design a magnetic nano-carrier for CDDP with magnetic targeting function to reduce the damage of CDDP to normal tissues in vivo and improve the therapeutic effect of cancer. Carboxymethyl chitosan (CMCS) is used to directly coat oleic acid (OA)-modified Fe3O4 nanoparticles (OA-Fe3O4 NPs) to create the nano-scale CMCS magnetic nanoparticles (CMCS/OA-Fe2O3 NPs), and CDDP loaded magnetic nanoparticles (CMCS/OA-Fe2O3 NPs/CDDP) are prepared by the bonding interaction between carboxyl groups on the surface of CMCS and the anticancer drug CDDP. The magnetic drug loaded nanoparticles are characterized, and the results show that the magnetic nanoparticles are successfully embedded in CMCS and loaded with CDDP, with the drug load of 43.65 ± 2.37%. MTT assay, flow cytometry and invasion assay are applied to evaluate the inhibitory effect of magnetic drug loaded nanoparticles to nasopharyngeal carcinoma (NPC) cells HNE-1. The results suggest that the magnetic drug loaded nanoparticles successfully prepared have significant inhibitory effect on HNE-1 cells in vitro. Therefore, the magnetic drug loaded nanoparticles prepared have a good therapeutic effect on NPC.

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3,3′,5′-Triiodothyronine inhibits ontogenetic development of iodothyronine-5′-deiodinase in the liver of the neonatal mouse

Acta Endocrinologica ◽

10.1530/acta.0.1190181 ◽

1988 ◽

Vol 119 (2) ◽

pp. 181-188 ◽

Cited By ~ 3

Author(s):

Doo Chol Han ◽

Kanji Sato ◽

Yuko Fujii ◽

Minoru Ozawa ◽

Hidehito Imamura ◽

...

Keyword(s):

Single Injection ◽

Inhibitory Effect ◽

Antagonistic Effect ◽

Time Dependent ◽

Dependent Manner ◽

Neonatal Mice ◽

Dose Dependent Decrease ◽

Dose Dependent

Abstract. To elucidate the effect of rT3 on iodothyronine-5′-deiodinating activity (I-5′-DA) in the liver of neonatal mice, rT3 was injected sc on the 5–8th day after birth and I-5′-DA in the liver was determined. A single injection of rT3 (0.01–1 μg/g) inhibited the ontogenetically developing I-5′-DA in a dose- and time-dependent manner. The inhibitory effect was reversible and specific for I-5′-DA. Lineweaver-Burk analysis revealed that the time- and dose-dependent decrease in the enzyme activity was due to a decrease in Vmax with no alteration in Km values (5 × 10−8 mol/l). The maximal inhibitory effect was observed at a dose of 1 μg rT3/g, whereas the inhibitory effect was diminished at greater doses (4–10 μg/g), probably owing to a contamination with T4 of the rT3 preparation administered. Furthermore, consistent with our previous in vitro findings, rT3 inhibited the I-5′-DA induced by T3 in the liver of neonatal mice. These findings suggest that rT3 inhibited I-5′-DA in the liver of neonatal mice by decreasing the amount of enzyme available to the substrate and that rT3 also elicited an antagonistic effect against T3 in the induction of I-5′-DA in vivo.

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